microbiology with diseases by taxonomy 5th edition test bank Archives

Microbiology with Diseases by Taxonomy Chapter 16 Answers

May 28, 2018 by Raju

Microbiology with Diseases by Taxonomy Chapter 16 Answers

Microbiology with Diseases by Taxonomy Answers

Microbiology with Diseases by Taxonomy Chapter 16 Answers 1CM
Human system is protected through the presence of both humoral and cell mediated systems

In humoral systenl, antibodies are synthesized to eliminate the presence of pathogens in the system, through different modes.
Presence of humoral immune system puts an end to number of pathogenic microorgamsms.

microbiology-with-diseases-by-taxonomy-chapter-16-answers-1cm

Microbiology with Diseases by Taxonomy Chapter 16 Answers 1CT
Advantage of lymphatic system to lack a pump:
Explanation
The absence of pump makes it sure that there is slow movement of lymph through the lymphatic vessels that is loaded with the lymphocytes. This increases the chances of microbes or antigens being identified as foreign lymphocytes; thus, eliciting an immune response against them. This is the main reason why an absence of pump aids in the betterment of the lymphatic system.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 1L
The differences in the structure of the antibodies enable it to bind to different antigens that possess different antigenic determinants. The formation of an antigen-antibody complex is highly important in eliminating an antigen from the host system.
The parts of the immunoglobulin are listed below:

Antigen binding.
Heavy chain variable.
Light chain variable region.
Light chain constant region.
Heavy chain constant region.
Transmembrane B cell receptor.
Variable region.
Constant region.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 1M

Plasma cell is differentiated B lymphocyte against specific antigen, which would initiate the process of secreting antibodies against antigen. The plasma cell is an antibody producing cell. It is produced from the B lymphocytes and plays an important role in defense. Hence, plasma cell is matched against D. Immunoglobulin.
Cytotoxic activity of T cell involves the usage of perforin and granzyme molecules. The perforin forms a tube like structure protruding the cell wall of the target cell, where granzyme enters and triggers apoptosis. Hence, cytotoxic T cell is matched against C.Perforin and Granzyme.
T-helper cell synthesizes the interleukin 4 (IL-4) molecules that would differentiate T helper cells from type 2 helper T cells. The type 2 helper T cells are involved in T dependent B cell activation process. Hence, Th2 cell is matched against B. Interleukin 4.
The dendritic cells are a part of the antigen presenting cells. The cells contain MHC class II molecules to present epitopes of antigens to lymphocytes in elimination target cell from the system. Hence, dendritic cell is matched against A. MHC II molecule.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 1MC

Antibodies cannot destroy a foreign graft, but could only aid to develop a catastrophic avalanche of other immune responses on the graft. Hence, option (a) is incorrect.
Antibodies aids in marking the foreign antigens, entering the host system thereby enabling immune cells including the B and T lymphocytes to identify the antigen and destroy them. This makes option (b) as the right choice.
Antibodies cannot be involved in killing any organisms or viruses. Their main aim is to mark the foreign antigen, which would then be taken care by the lymphocytes. Hence, option (c) is incorrect.
Cytokine synthesis would not be activated through the presence of antibodies alone. It is only the antigen-antibody complex that would aid in the synthesis of cytokines that would elicit an immunological response in eliminating the antigen from the host system. Hence, option (d) is incorrect.
Antibodies do not have any impact on T cell proliferation. Once the antigen is marked by the antibody, it is the T-helper cell that would recognize the antigen and would inturn stimulate the differentiation and multiplication of T-cytotoxic cells. Since it is an indirect action option (e) becomes incorrect.
Antibody functions to (b) mark invading organisms for destruction.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 1MTF
MHC class II molecules:
Explanation
The MHC (Major histocompatibility complex) class II molecules form an integral part of the antigen presenting cells, but not by T lymphocyte. The process is mediated through MHC class II molecule, the antigen presenting cell presents the antigen to T lymphocytes.
Thus, the given statement, “MHC class II molecules are found on T-cells” is False.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 1SA
Antigen processing is an essential prerequisite, for immune response:
Explanation
Antigen processing is prerequisite for identifying antigens that are of indigenous nature. Consider a case where antigen would be growing actively inside a host cell. In such situation, the presence of MHC class I molecules, the foreign antigens could be identified on the cell wall. The cells are processed and the antigens would be presented to T lymphocyte through MHC class II molecules. Hence, it is highly clinical that the antigen processing is highly essential for antigens of endogenous nature.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 2CT
Contraction between innate defenses with adaptive immunity:
Explanation
microbiology-with-diseases-by-taxonomy-chapter-16-answers-2ct

Microbiology with Diseases by Taxonomy Chapter 16 Answers 2M

Administration of antitoxin in the form of antibodies, developed against specific toxin is an example of artificially acquired passive immunotherapy. Hence, artificially acquired passive immunotherapy is matched against D. Administration of antitoxin.
The development of antibodies naturally against a specific antigen or allergen is termed naturally acquired immunity. Development of IgE antibody against the allergen pollen is one such example. Hence, naturally acquired active immunity is matched against A. Production of IgE in response to pollen.
Injection of immunoglobulins into another host naturally without the aid of medical devices is termed naturally acquired passive immunity. The passage of antibodies from the mother’s breast milk to child is an example of this type. Hence, naturally acquired passive immunity is matched against B.Acquisition of maternal antibodies in breast milk.
Deadly toxins when incorporated through injection (in a naïve form) without any natural infection, could elicit animmune response. Hence, artificially acquired active immunity is matched against C. Administration of tetanus toxoid.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 2MC

The class II MHC molecules are present on the exterior of the helper-T cells; also upon binding with the antigen, it would activate the helper-T cells and not the cytotoxic-T cells. Hence, option (a) is incorrect.
Since the class II MHC molecules are found on the outer surface of the helper-T cells. They would activate only the helper-T cells and not the cytotoxic-T cells. This makes option (b) incorrect.
MHC class II molecules would be activated by the antigens presented to them through the antigen presenting cells like the macrophages. Antibodies do not have any role in the activation of the T cells. Hence, option (c) is incorrect.
Though it is the T-helper cells that are being activated by the MHC class II molecules, the molecules are present on the outer surface of the helper-T cells. This makes the molecule an exogenous one. This criterion makes option (d) as incorrect.
The MHC class II molecules are present exogenously on the helper-T cells. Once the antigen presenting cells presents antigens to these cells, the helper-T cells would be activated against that specific antigen. This would in turn activate the cytotoxic-T cell which would eliminate the antigen from the system. Hence, option (e) is the right choice.
The right option is (e) exogenous antigens, helper T cells.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 2MTF
Apoptosis:
Explanation
Apoptosis is the term associated with destroying self-cellular components either during a viral infection or during clonal deletion. Cells undergo transformation in normal body cell into neoplastic or cancer cell that is not controlled by cell normal process. Moreover, cells escape from normal body surveillance though abnormal cell and body immune system destroys it.
Thus, the given statement, “apoptosis is the term used to describe cellular suicide” is True.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 2SA

The vertebrate immune system shows two types of responses termed the humoral and the cell-mediated immune response. The type of response depends on the type of the antigen that evades the host. Though these two immune responses are demarcated as separate, the body uses both the mechanisms simultaneously to eliminate any pathogen. The difference lies in which type of immune response predominantly acts to eliminate a pathogen/antigen.
Humoral immune response involved antibodies and is mediated by antigen activated B cells called plasma cells. They are specific to each type of antigen and the response takes time to be initiated. It generally takes at least 3 – 4 days for the B-cells to respond and synthesize specific antibodies against a pathogen.
Antibodies are synthesized against circulating antigens. Therefore, they contain extracellular or exogenous antigens.
Cell mediated immune responses involve cells like T-lymphocytes, macrophages, and neutrophils which act directly on the target cell and destroy it. They cell mediated immune system either directly recognize certain patterns of antigens on the target cells (like peptidoglycan or anionic polymers, which are unusual and are not found on the healthy self-cells) through their pattern recognition receptors; or recognize aberrant MHC (major histocompatibility complex) proteins on the cell surface; or they recognize antigens presented in context with MHC.
Thus, cell mediated immune responses mainly aim at targeting cells infected with intracellular parasites, cells that became abnormal, or aberrant cells.
Since pathogens can be either extracellular or intracellular, the two arms of immune responses are required to contain them effectively. The way the immune system deals with these two types of antigens is different. While cell mediated immune responses act quickly and inhibit the infecting pathogens from further multiplying, humoral immune responses come into play after a period of activation. Cell-mediated responses are less specific and thus, comparatively less efficient in containing a pathogen whereas humoral immune responses are highly specific and are efficient and effective in eliminating a pathogen.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 3CT
Benefit of requiring immune system to process antigen to body:
Explanation
Antigens are not supposed to be identified by the immune system of the host. At times, they would escape the immune system through their complex structure. In order, to make sure that the complex structure of the antigens is broken down to simpler substances. In addition, they are made available to immune system to elicit an effective immune response against the antigen that is being processed. This increases the chance of antigen being acted against by host immune system.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 3MC

Destruction of virus infected cell is through cell mediated cytotoxicity, occurs through the cytotoxic T lymphocyte. One such activity of the cytotoxic T lymphocyte is the destruction of virus infected cells. Destruction of virus infected cells has no coincidence with the rejection of skin graft, though both skin grafts, and virus infected cell are rejected by cell mediated cytotoxicity. This proves that option (a) is incorrect.
Tolerance is the term used to denote autoimmune diseases. Self-tolerance is highly important as the lymphocytes should not act against self-cells. Since, the cells belonging to the host would be identified through their MHC molecules, the host’s self-cells cannot be rejected. Tolerance and graft are diagonally opposite terms as graft need not necessarily contain the same MHC molecule. Hence, option (b) is incorrect.
Antibody mediated immunity, takes time to react against a specific antigen. Though rejection of graft would also be accompanied by the action of humoral immune response it cannot be rejected outright by the action of immunoglobulin alone. This makes option (c) as the incorrect.
Primary immune response is conferred when the antigen is inherited during the first time. Secondary immune response is one when the antigen is encountered the next time, where the memory cells attack the antigens immediately. Since, the graft is rejected in the first instance itself; option (d) may not be the right choice.
Cell mediated immune response is the primary response through which a graft would be rejected immediately. The response is as a result of the cytotoxic activity of the T lymphocytes. Hence, option (e) is the right choice.
Thus the right choice is (e) a cell-mediated immune response.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 3MTF
Lymphoid system includes tissue aggregates and organs composed of lymphoid tissue.
The five main cell types of lymphatic tissues are natural killer cells (NK cells), T lymphocytes, B lymphocytes, macrophages, dendritic cells, and reticular cells.

T lymphocytes cannot recognize pathogens they require antigen presenting cells.
B lymphocytes produce antibodies. They generate receptor diversity of immunoglobulins

T Lymphocytes are of two types based on the type of glycoprotein that is associated on their cellular surface. The lymphocyte that contains the CD8 (CD – Cluster of differentiation) molecule is cytotoxic T lymphocyte, whereas CD 4 lymphocyte is helper T lymphocyte. Thus, the statement, “lymphocytes with CD8 glycoprotein are helper T cells” is False.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 4CT
Immunological impairments that results in the following are:
Explanation

Class I MHC molecules are developed by nucleated cells in the body. The molecules present the processed antigens (intracellular antigens) to immune system and deficiency in synthesis of class I MHC molecule is susceptible to infection.
Class II MHC molecules are present on the surface of the helper-T cells. The antigen presenting cells would present the processed antigens to class II MHC molecules, which would elicit an immune response against the antigen provided. The presence of class II MHC molecule would ensure that any false activation of the immune system is put to rest, thus acting as a regulatory system.
T-cell receptors (TCR) are found on the surface of the T-cells that binds specifically to a particular antigen. The antigens bind to TCR on activation; thus, T-cells elicit cell mediated immune response against the antigen. Without which the host system would lack the cell mediated immune response. Similarly, T-cells and B-lymphocytes are also associated with receptors that are specific against a particular antigen. The presence of B cell receptors is highly essential in eliciting humoral immune response. Without, which the host system would lack the humoral immune response.
Interleukin-2 (IL-2) is the molecule that aids in the proliferation of lymphocytes after activation by an antigen, by attaching to IL-2 receptor of lymphocyte. Without the presence of receptor for IL-2 the activated lymphocytes will not undergo multiplication to form a clone of cells, effective against the antigen.
Interferon-? (IFM- ?) is essential in activation of cytotoxic-T lymphocytes. Activation of T lymphocytes is important in eliminating the intracellular pathogens of the host system. Any deficiency in the presence of IFN- ? molecule would retard the activation of cytotoxic T lymphocytes; thus, reducing the effect of cell mediated immunity.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 4MC
Microorganism from a normal biota would be termed an antigen, but not an auto-antigen. Hence, option (a) is incorrect.
When the host immune system elicits a response against its own body component, then the host cell is known to have become an auto-antigen. This makes option (b) as the right choice.
An artificial antigen is one where an antigen would be engineered for raising immunological response without actually giving the symptoms of the disease. Hence, option (c) is incorrect.
Carbohydrate that would be taken in as a normal food proportion cannot be considered as an antigen. There are situations where certain carbohydrates would be considered antigen, but definitely not as an auto-antigen. Hence, option (d) is incorrect.
A nucleic acid transferred from a virus is capable of destroying the host system through an infection. Prokaryotes are given immunity against such nucleic acids entering through the restriction modification system. Under such circumstances the nucleic acid would be considered only as an antigen and not as an auto-antigen. This makes option (e) incorrect. Thus the right choice is (b) a normal body component.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 4MTF
Immunoglobulins are antibodies that are secreted by B lymphocytes and immunity conferred is termed as humoral immunity. The cytotoxic T lymphocytes are directly involved in the removal of target cell.
The process is mediated by the following:

Direct cytotoxicity.
Complement mediated cytotoxicity.

However, type of helper T cell would aid in the activation of B lymphocytes, making them secrete immunoglobins, but T cell is not involved in antibodies secretion.
Thus, the statement, “cytotoxic T cells secrete immunoglobulin” is False.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 5CT
Effects of human immunodeficiency virus on humoral and cell-mediated immunity:
Explanation
The helper-T cells have control over both cell mediated and humoral immune responses. While, the former has a pathway that could be activated without the presence of helper-T cells, cell mediated cytotoxicity would be lost if the helper-T cells are destroyed, as a result of human immunodeficiency virus (HIV) infection. The virus specifically targets helper-T cells; thus, reducing overall effects of immune responses.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 5MC

Perforins are produced by the natural killer cells, which would destroy the antigens by forming channels that would trigger apoptosis. The activity of the natural killer cells would be initiated by the antibody-antigen complex. This makes option (a) as the correct choice.
Immunoglobulins are antibodies that are involved in their specific attachment to the antigens. Immunoglobulins form a part of the humoral immune response (or) antibody mediated immune response thus making option (b) as the incorrect choice.
Complement activation is a part of the humoral immune response where the activated complemented system destroys the target cell through the formation of membrane attacking complex (MAK) on the whole cell antigen. The MAK forms pores on the pathogen, leads to change in the osmatic pressure balance. This makes option (c) as the incorrect choice.
Cytokines are components, which are used by the human system in trafficking the lymphocytes to a particular location. They are indirectly involved in aiding cell mediated cytotoxicity, but are not a direct reason for it. Hence, option (d) becomes the incorrect choice.
Interferons are cytokines that has the potential of acting both as a signal material as well as in emphasizing phagocytosis of the infected cells. Since it is an indirect factor involved in directing cell mediated cytotoxicity, option (e) becomes an incorrect choice. Thus the right choice is (a) perforin.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 5MTF
Immunity conferred to human system is mediated by two basic types. They include the following types:

Humoral immunity
Cell mediated immunity.

In humoral immunity, B lymphocytes are involved and in cell mediated immunity T lymphocytes are involved. B cells produce immunoglobulins or antibodies that would be circulated in the blood. Since, blood is known as humors, the type of immunity conferred through B lymphocytes is termed as humoral mediated immune response. Moreover, there is no cell to cell contact in humoral immune response. In cell mediated immunity, cytotoxic T lymphocyte would be in direct contact between T lymphocyte and target cell.
Thus, the statement, “secretion of antibodies by activated B cells is a form of cell-mediated immunity” is False.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 6CT
Person who fails to make MHC molecules occurs:
Explanation
The MHC class I molecules are required for presenting the processed intracellular pathogens. Moreover, it is only process through, which the class II MHC molecules represents antigen presenting cells to lymphocytes. Hence, without the presence of the MHC molecules the host system lacks the presence of acquired immunity. Thus, the person is prone to all infections.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 6MC
The T-lymphocytes are those that accounts for about 70-85% of the total lymphocyte population. Hence, option (a) becomes the right option.

The B-lymphocytes are a major part of the remaining lymphocyte population. They are found circulating the blood. Since they are found in a very small quantum, option (b) becomes incorrect.
Plasma cells are those multiplying B-lymphocytes that are ready to produce antibodies specifically against a particular antigen. Since they are only a part of the B-lymphocytes, option (c) becomes incorrect.
Memory cells are those that act in reproducing the antibodies that have once formed against a specific antigen. Normally the memory cells would be less in quantum, and once the host system comes in contact with the same antigen again. The memory cells would produce the plasma cells that would synthesize the antibodies. This makes option (d) as the incorrect choice.
The concentration of each and every component of the lymphocytes is predetermined and they are not found in the same concentration. This makes option (e) as the incorrect choice. Thus the right option is (a) T cells.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 7CT
Five different classes of immunoglobulins:
Explanation
Immunoglobulins are present throughout our immune system. They are found circulating through the blood. The existing immunoglobulin has different shapes and is conferred to have different functions. They are as follows:

Immunoglobulin M acts as antigen binding sites on B lymphocytes, due to their multivalent nature. Moreover, they are highly efficient when secreted during an immune response.
Immunoglobulin G is the highly synthesized immunoglobulin, also known as serum antibody. It is found secreted in the body fluids, blood, and fluids of tissues to react with antigens.
Immunoglobulin A is transferred from mother to fetus through placenta. The molecule is also present in tears and mucous where the molecule reacts with antigens.
Immunoglobulin E is the molecule that is capable of eliciting an allergic response by attaching itself to mast cells. The molecule binds to the mast cell through constant region. Thus, leaving free antigen binding site. When the antigen (during second contact) binds to the antibody, it triggers the mast cells to degranulate by enabling allergic response.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 7MC

IgG molecules are the most found antibody in the system. The molecule is involved in antibody mediated immunity and is commonly found in circulating blood. Hence, option (a) is incorrect.
IgM molecule is a pentamer composed of five IgG molecules. It is involved in agglutination, neutralization and in complement activation. Since these activities could only be done in the circulating blood. Hence, option (b) becomes incorrect.
IgA constitutes about 12% of the total serum antibody. They are found lining the respiratory, gastrointestinal, urinary, and reproductive tracts. Hence, option (c) is the right choice.
IgE act as signal molecules that attach to receptors on the eosinophil triggering the release of histamines. This makes option (d) as incorrect.
IgD are not secreted, but are membrane bound antigen receptors on B cells. This makes option (e) as the incorrect choice. Thus the right option is (c) IgA.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 8CT
Ideal properties of materials implanted in the body are:
Explanation
Metal bone pins and plastic do not have an antigenic status that would elicit an immune response. Moreover, they are neither capable of causing any infection on their own. Since, MHC molecules can identify the biomolecules they do not elicit any immune response against the artificial devises implanted; thus, making it a safe entity.
Additionally, material that is not capable of eliciting an immune response proves to be a better article to be used in implantation. The only thing that needs to be kept in mind is that the material should not allow infection to pass through, being implanted.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 8MC

MHC class I molecules would be found on all nucleated cells. Since, red blood cells lack nucleus they also do not possess the class IMHC molecule on them. This makes option (a) as the incorrect choice.
Antigen presenting cells would be bearing the MHC class II molecule and not the class I molecule. This makes option (b) as the incorrect choice.
Neutrophil being an antigen presenting cell would be bearing the MHC class II molecule and not the MHC class I molecule. This makes option (c) as the incorrect choice.
The MHC class I molecules are present on all the nucleated cells of the host including the skin and muscles. Hence, option (d) is the right choice.
Dendritic cells contain MHC class II molecules. They are antigen presenting cells that acts on the antigens and presents the antigen to the lymphocytes. This makes option (e) as the incorrect choice.
Thus the right option is (d) all nucleated cells.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 9CT
The membranous and non-membranous organelle prevalent in plasma cells:
Explanation
The plasma cells are involved in secretion of antibodies in the system. They have high quantum of rough endoplasmic reticulum, owing to their function. The ribosome that forms an integral part of the endoplasmic reticulum is major non-membranous organelle present in the plasma cell. However, plasma cells are twice as the size of an inactive B-lymphocyte, primarily. This is because of their function in synthesizing antibodies based on presence of endoplasmic reticulum and Golgi complex. The endoplasmic reticulum aids in the production of immunoglobulins, while the Golgi complex would transport them across the cell membrane.
Thus, endoplasmic reticulum and Golgi complex are highly important membranous organelles in plasma cells.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 9MC

B cells are synthesized in the bone marrow, which after maturation would be an integral part of the lymph node. Hence, option (a) becomes the right choice.
Spleen is an organ, where the blood filters toxic and other antigenic substances. In order to tackle the antigens present in the blood, the filtered component would be tackled by the B lymphocytes through the production of immunoglobulins. Thus option (b) becomes the right choice.
Red bone marrow is the place where the B cells originate, thus making option (c) as the right option.
B cell is an integral part of Mucosal Associated Lymphoid Tissues (MALT) of the intestinal tract, majorly to tackle the antigens coming through food intake. Hence, option (d) becomes the right choice. Thus the right choice is (e) all of the above.

Microbiology with Diseases by Taxonomy Chapter 16 Answers 10MC

The cytotoxic T cells would recognize the antigens presented to them through the MHC molecules. The helper T cells would enhance the effect of the established linkage between the MHC molecules, and that of the cytotoxic T cells aiding them to multiply. This makes option (a) as the right choice.
The helper T cells are those that aid in the activation of the cytotoxic T cells when the antigens are presented through a MHC molecule. B cells are in no way associated in presenting the antigen to the T cells. This proves that option (b) is incorrect.
Interleukin-2 that is secreted by the dendritic cells aids in the stimulation of the helper T cells to become a clone of type I T helper cells (which in turn secrete interleukin 2.) Interleukin 2 is primarily responsible for the differentiation of the T cells, and the formation of helper T cells. This makes option (c) as the incorrect choice.
Granzyme is involved in the apoptosis of target cells through cell mediated cytotoxicity through the other molecule perforin. They are in no way associated with the presentation of the antigen to the cytotoxic T cells. This makes option (d) as the incorrect choice. Thus right option is (a) MHC proteins.

Microbiology with Diseases by Taxonomy Chapter 15 Answers

May 28, 2018 by Raju

Microbiology with Diseases by Taxonomy Chapter 15 Answers

Microbiology with Diseases by Taxonomy Answers

Microbiology with Diseases by Taxonomy Chapter 15 Answers 1CM
The terms given in the question are given below:

Adherence
Chemotactic factors
Chemotaxis
Dendritic cells
Elimination
Eosinophils
Exocytosis
Ingestion
Killing
Lysosome
Macrophages
Neutrophils
Opsonins
Phagolysosome
Phagosome

The concept map showing the process of phagocytosis is given below:
microbiology-with-diseases-by-taxonomy-chapter-15-answers-1cm

Microbiology with Diseases by Taxonomy Chapter 15 Answers 1CT
Mr. J received a burn on his arm while handling chemicals. The chemicals reacted with the skin to give painful, red and swollen lesions. Mr. C suffered a cut on his foot which became infected. He too suffered the same symptoms of redness and swelling along with pain.
In Mr. J’s case, the inflammation seen is the body’s response to the damage done by chemicals. In Mr. C’s case, the inflammation seen is due to the response of the body to microbial invasion. The similarity is that both are experiencing damaged tissues but the agent of damage differs in each case.
No, Mr. C should not take the same medicine that Mr. J used. When the body fights against microbes, it stores the information in memory cells. This helps the body to fight faster in the event of a second attack by the same microbe. Since inflammation is a response of the body, it should not be suppressed too much. This would be suppressing the immune system of the body.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 1L
The labeled parts of the diagram showing the different events in the process of phagocytosis are:
microbiology-with-diseases-by-taxonomy-chapter-15-answers-1l
In the process of phagocytosis, we see 6 steps:

Chemotaxis
Adherence
Ingestion
Maturation
Killing
Elimination

In the step of chemotaxis, the phagocyte is attracted towards the microbe. In the step of adherence, the phagocytic cell binds to chemicals on the surface of the microbe. In the step of ingestion, the microbe is engulfed by the phagocyte. In the step of maturation, fusion with a lysosome occurs. In the step of killing, the microbe is degraded by the enzymes in the lysosome. In the step of elimination, the remnants of the digestion are eliminated by the process of exocytosis.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 1M1
The term “inflammation” matches with the phrase “second line of defense.” The second line of defense consists of cells, antimicrobial chemicals, and processes like inflammation and fever.
It is a nonspecific response to the damage of tissues. The damage in tissues can be due to a variety of reasons like heat, cuts, chemicals, and pathogens.
There are two types of inflammation: Acute and Chronic.
Acute inflammation is short lived and results in the removal of the cause of the inflammation. In chronic inflammation, damage in tissues occurs, which can lead to the death of the tissues. Both acute and chronic inflammation shows the same symptoms of redness, heat, pain and swelling.
Hence, the correct option is B. second line of defense.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 1M2
The term “Goblet cell” matches with the phrase “secretes mucus.” These cells come under the first line of defense of the body.
Goblet cells are present amidst the cells of the mucous membrane. These cells secrete sticky mucus which helps to trap pathogens. The goblet cells are epithelial cells which secrete mucus. These cells are usually found amid the epithelial lining of the respiratory and the intestinal tracts. These cells are not macrophages or phagocytes.
In some locations, ciliated cells are present in addition to goblet cells. These cilia help to push out the pathogens trapped in the mucus.Hence, the correct option is J. secretes mucus.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 1MC
The goblet cells are epithelial cells which secrete mucin. These cells are usually found amid the epithelial lining of the respiratory and the intestinal tracts. These cells are not macrophages or phagocytes. They are also not present in the epidermis. The phagocytes of the epidermis are known as dendritic cells. Hence, the option (b) is incorrect.
Alveolar macrophages are present in the lungs. These are not wandering macrophages, but fixed in the same tissue. They are not present in the epidermis. The phagocytes present in the epidermis are known as dendritic cells. Hence, the option (c) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 1MTF
The statement given is “The surface cells of the epidermis of the skin are alive.” The above statement is false.
The outer layer of the skin, the epidermis consists of dead cells. The epidermis consists of multiple layers of cells which are tightly packed. The topmost layer consists of cells which are dead and dry. These cells are shed continuously, which do not allow most microorganisms to settle on the skin.
The lowest layer of the epidermis contains cells which continually divide, pushing new cell towards the surface. These new cells are pushed till they reach the surface. By the time they reach the surface, they die and are later shed as skin flakes. Hence, the surface layer of the epidermis contains dead and not living cells.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 1SA
In order for a pathogen to cause disease, the three things which must happen are:

Gain access into the body:
Pathogens must be able to gain access into the body of the host. This can be done by entering through some portal of entry. It can also be established by penetrating the skin of the host. They either use the existing routes of entry or create new routes.
Attach to host cells:
Attachment of pathogens to host cells is known as adherence. Unless a pathogen attaches to a host cell, it cannot infect that particular host cell. The pathogen usually has some proteins and markers on the surface which attaches to the surface of the host cell.
Escape the defense mechanisms of the body and cause damage:
The human body has three levels of defense. The first line of defense consists of the skin, mucous membranes, lacrimal apparatus, normal flora, and antimicrobial peptides. The second line of defense consists of the cells of the blood, phagocytosis, nonphagocytic killing, nonspecific chemical defenses like the complement system, and other processes like inflammation and fever. The third line of defense is adaptive immunity which is specific for each pathogen.

After escaping all these defenses, the pathogen has to be able to inflict damage on the host cell to be able to cause infection.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 2CT
When a person does not produce C3 and C5 proteins, the following changes occur:
Absence of C3:
Since C3 is a vital part of the complement cascade. The activation of C3 produces the effects of opsonization and inflammation. This leads to the formation of C5 convertase which produces the effect of inflammation. All these effects are absent if C3 is missing. The final formation of the membrane attack complex does not occur. Hence, the complement system does not function properly.
Absence of C5:
The absence of C5 leads to the absence of the C5 convertase complex. The complement cascade system works perfectly till this step. The effects of inflammation and opsonization are seen since C3 is produced. But the formation of the membrane attack complex does not occur.
When both the C3 and C5 proteins are not produced, then the complement system does not function properly. Since C3 and C5 are the vital and major components of the complement cascade, the absence of these proteins leads to improper functioning of the complement system.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 2M1
The term “monocytes” matches with the phrase “second line of defense.” The second line of defense consists of cells like monocytes, antimicrobial chemicals, and processes.
Monocytes are a member of the white blood cells in the blood. They are also a part of the innate immune system. When monocytes mature, they give rise to macrophages and dendritic cells. In the innate immunity, both macrophages and dendritic cells play an important role to protect the body from the various pathogens.
Both dendritic cells and macrophages play a role in phagocytosis. Hence, monocytes are a part of the second line of defense. Since macrophages are nonspecific phagocytic cells, they form the second line of defense of the body. Hence, the correct option is B. second line of defense.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 2M2
The term “lysozyme” matches with the phrase “breaks bonds in bacterial cell wall.” Lysozyme comes under the first line of defense.
Lysozyme is an enzyme present in the dermis of the skin. Lysozyme is an enzyme which destroys the cell wall of bacteria. It breaks down the bonding between the building blocks of the cell wall. Cells without a cell wall are susceptible and are killed quite easily.
The mucous in the nasal epithelium also contains lysozyme. The enzyme is present as the first line of defense to lyse any pathogens which enter the nose. Some microbes can be resistant to the action of lysozyme. Hence, the correct option is E. breaks bonds in bacterial cell wall.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 2MC
Mucus secreting membranes are found in the urinary system, respiratory passages, and digestive cavity.

Mucus secreting membranes are found in the urinary system, which includes the urethra and the urinary tracts. Mucus membranes are moist and have two layers. The topmost layer is the epithelium while the deeper layer is the connective tissue. The mucus membrane is a common portal for most pathogens. Hence, the option (a) is correct.
The digestive cavity is also lined by mucus membranes. Since mucus membranes are an easy portal for microbes, the topmost cells are continually shed. This removes the organisms attached to the topmost layer of the mucus membranes. Dendritic cells are present below the mucus epithelium and phagocytize pathogens. Hence, the option (b) is correct.
The respiratory passages are also lined by mucus membranes. In the mucus membranes of the trachea, goblet cells are present. These cells produce a sticky substance called mucin. The respiratory passages also contain ciliated cells which contain cilia. These cilia are useful in trapping pathogens and pushing them out of the body. Hence, the option (c) is correct.
The urinary system, the respiratory passages and the digestive tracts all possess mucus membranes.
Hence, the correct option is (d) all of the above.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 2MTF
The given statement “The surface cells of mucous membranes are alive” is true. These mucous membranes cover all body cavities which open to the outside. The mucous membrane is also part of the first line of defense of the body. It acts nonspecifically against pathogens.
Mucous layers have two layers, one is the epithelium and the other is a deeper connective tissue. The surface cells of the mucous layers are alive and play a role in the processes of diffusion of gases and nutrients.
One way in which pathogens are kept from entering the body, is the tight packing of epithelial cells along with constant, shedding of the cells of the top layer. When the topmost cells are shed, the pathogens attached are also shed.
Some mucous membranes, especially those in the respiratory tract contain cilia which help to trap pathogens in the waves of cilia. The pathogens are later propelled out of the body. Goblet cells are also present amidst the cilia which secrete a sticky substance called mucus which also traps pathogens.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 2SA
A phagocyte knows it is in contact with a pathogen instead of another body cell in the following way:
Chemotaxis:
The secretions from microbial cells and the components of the cells attract phagocytes. These chemical secretions attract phagocytes to the microbial cells in the process of chemotaxis. In the case of phagocytosis, positive chemotaxis is seen where phagocytes are drawn towards the microbial cells.
Adherence:
The process of attachment to the microbial cell is known as adherence. This attachment is achieved when the surface proteins of the microbial cell attach to the proteins on the surface of the phagocytes. Phagocytes bind to complementary chemicals like glycoproteins which are found on microbial cells. These microbe-specific glycoproteins are not found on the surface of host cells.
These are the two ways in which a phagocyte can differentiate between a normal host cell and a microbial cell. This ability to differentiate helps to protect the body’s own cells from the process of phagocytosis. If phagocytes did not have this ability to differentiate, all the host cells would have been phagocytized.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 3CT
Mrs. M has diabetes for 40 years. The small blood vessels in her feet and toes have been damaged due to the disease. Since her blood vessels are damaged, the circulation in her feet and toes is impaired.
Since her circulation is impaired, this indicates that the blood flow to her legs is less. Mrs. M is quite susceptible to infections in her legs and toes since she cannot receive adequate immune cells due to lack of circulation.
Cells like phagocytes and the proteins of the complement cascade are all transported through the blood. When the circulation of blood cells is low, these cells also cannot reach the legs on time in the event of any injury.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 3M1
The term “lactoferrin” matches with the phrase “second line of defense.” The second line of defense consists of cells and proteins in the blood, antimicrobial chemicals, and processes.
The protein lactoferrin is a member of the transferrin proteins. It transfers iron molecules into the cells and controls the free iron levels in the blood. Apart from this function, it also has antibacterial and antiviral activities.
As it controls the free iron levels in the blood, it does not allow microbes to absorb this iron for their own use. It prevents the microbial cells from stealing the iron from the body.
Hence, the correct option is B. second line of defense.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 3M2
The term “stem cell” matches with the phrase “generative cell with many types of offspring.”
Stem cells are those cells which can give rise to any cell as a progeny. In the chapter of innate immunity, we see the role of stem cells in the first line of defense of the body. The mucous membranes of the body are a first line of defense.
The mucous membrane has a topmost moist layer which is an easy portal for microbes. But, the cells of the top layer of the mucous membranes are continuously shed. This is due to stem cell division.
When the topmost layer of cells is shed, the pathogens attached are also shed. This removes pathogens from the body. Hence, the correct option is G. generative cell with many types of offspring.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 3MC

The complement system does involve serum proteins, which play a role in nonspecific defense of the body. A group of proteins can work in three pathways to kill the invading pathogen. The end result of the action of the proteins of the complement system is the cell lysis of the pathogens. This defense is called a nonspecific defense because there is no specificity between the pathogens and the serum proteins of the complement system. The pathogens are recognized and killed. Hence, this option is correct.
The production of antigens and antibodies does not involve the complement system. Antibodies are produced by B cells, which are produced by lymphocytes. Self-antigens are produced in the body as proteins in specific cells of the body. Hence, the option (a) is incorrect.
Leukocytes are the cells which can distinguish foreign cells from body cells. The complement system is not a set of genes, which can differentiate between foreign cells and body cells. The complement system is a set of serum proteins, which are involved in nonspecific defense of the body. Hence, the option (c) is incorrect.
Phagocytes are the cells, which remove the undigested remnants of microbes. The undigested parts are removed by the process of exocytosis. The complement system does not participate in the elimination of undigested remnants of microbes. The complement system is a set of serum proteins, which are involved in nonspecific defense of the body. Hence, the option (d) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 3MTF
The given statement “Wandering macrophages experience diapedesis” is true. Macrophages are phagocytic cells, which function as the second line of defense after the pathogen has entered the body. The first line of defense sometimes fails and thus the body has its second line of nonspecific defense cells.
Some macrophages in the body are fixed, while others are wandering macrophages which travel in the blood. The fixed macrophages have different names based on their specific location. The macrophages of the lungs are called alveolar macrophages, while the macrophages of the brain and spinal cord are called microglia.
Wandering macrophages are the ones which experience the process of diapedesis. When a cut occurs in the skin, many pathogens enter the skin layers. When this happens, the macrophages in the blood move out of the blood stream and into the tissues. The movement of these macrophages past the cells of the blood vessel and into the tissues is known as diapedesis.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 3SA
The three characteristics of the epidermis that make it intolerable for most microorganisms are:

Tightly packed cells:
The epidermis consists of many layers of tightly packed cells. This acts as a physical barrier to most microbes. Unless the skin has a gash or cut or a puncture, most microbes cannot cross the first defense of the skin.
Regular sloughing off of the topmost layer:
The topmost layer of the epidermis is regularly sloughed off. The topmost layer consists of dead and dry cells which are sloughed off. The pathogens attached to these cells are also pushed off along with the dead cells. This is another method in which the skin regularly keeps the epidermis free from pathogens.
Phagocytic cells called dendritic cells:
The epidermis contains phagocytic cells called dendritic cells. These cells have slender fingers which surround cells forming a sort of network. These dendritic cells can phagocytize pathogens nonspecifically. They also play a role in adaptive immunity where specific response to specific pathogen is seen.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 4CT
The chart of a patient shows that the percentage of eosinophils in his blood is 8% of the total WBC. Eosinophils are usually elevated during worm infestations or allergies. Normally, we would suspect that the main reason for the elevated number of eosinophils is an allergy.
The suspicions of the reason for the eosinophilia would definitely change with the knowledge that the patient has been living in Africa for the past three years as an anthropologist. The patient had gone to Africa to study the anthropology of an African tribe.
Hence, we can safely assume that the eosinophilia seen is due to helminth or worm infestations. The normal percentage of eosinophils is 2-4%.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 4M1
The term “fever” matches with the phrase “second line of defense.” The second line of defense consists of cells, antimicrobial chemicals, and processes like inflammation and fever.
Fever is usually caused due to pyrogens. These pyrogens are chemicals, which reset the thermostat in the hypothalamus to a higher temperature. Pyrogens can include toxins released from bacteria, cytoplasmic contents of bacterial cells released after lysis, and chemicals released by phagocytes.
The hypothalamus is a part of the brain which controls the temperature of the body. Fever is a symptom seen when the body temperature rises above 37 degrees centigrade. Fever has side effects like malaise, tiredness, and body aches.
The symptoms of fever remain as long as pyrogens are present. When the infection starts to come under control, the level of pyrogens reduces and the body temperature is slowly reset to normal.
Hence, the correct option is B. second line of defense.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 4M2
The term “dendritic cell” matches with the phrase “devours pathogens in epidermis.” Dendritic cells come under the first line of defense.
Dendritic cells are present in the epidermal layer of the skin. These are phagocytic cells which are formed by monocytes. Dendritic cells have slender processes which extend among cells. These slender processes form a continuous network which traps pathogens.
These cells are nonspecific for pathogens and form the first line of defense. Dendritic cells also play a role in adaptive immunity.
Hence, the correct option is D. devours pathogens in epidermis.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 4MC
The cleavage of C5 to form C9 is seen in all the three pathways as a common step. The protein C5 is cleaved into C5a and C5b. the C9 protein is a part of the membrane attack complex, which causes lysis of the microbial cells. Hence, the option (b) is incorrect.
The step of binding to mannose on the microbial cell wall is seen in the lectin pathway but not in the alternate pathway. Lectins are chemicals, which bind to the mannose on the surface of the microbial cell wall. When lectins bind to mannose, it triggers a complement cascade by the cleavage of C2 and C4 proteins. Hence, the option (c) is incorrect.
The recognition of antigens bound to specific antibodies is seen in the classical pathway but not in the alternate pathway. In the classical pathway, the proteins C1, C2 and C4 act to form a complement cascade. Hence, the option (d) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 4MTF
The given statement “Monocytes are immature macrophages” is true. Monocytes are large leukocytes which are agranular. The nuclei in monocytes are slightly lobed in appearance. Monocytes are immature macrophages; they mature into macrophages after they leave the blood.
Monocytes are a member of the white blood cells in the blood. They are also a part of the innate immune system. When monocytes mature, they give rise to macrophages and dendritic cells. In the innate immune system, both the dendritic cells and macrophages have an important role to fight against the various unprocessed antigens.
Both these cells play a role in phagocytosis. Hence, monocytes are a part of the second line of defense. Since macrophages are nonspecific phagocytic cells, they form the second line of defense of the body.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 4SA
The role of Toll-like receptors in the response of innate immunity can be described below:
These Toll-like receptors or TLRs are produced by phagocytic cells and are present as integral membrane proteins. These TLRs trigger the immune response of the body to the presence of molecules usually present in pathogens and absent in humans.
Examples of these foreign molecules include peptidoglycan, flagellin, double stranded RNA, single stranded RNA, and other molecules.
The TLRs recognize these molecules and initiate a number of immune responses. A few of them include:

Apoptosis
Secretion of interferons
Production of chemical stimulants

The recognition of foreign particles by TLRs is a very vital part of the innate immune response. If these TLRs do not recognize these foreign particles, the body would soon be filled with such molecules.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 5CT
There are two types of agranulocytes in the blood. One is a monocyte and the other is a lymphocyte. Monocytes constitute about 3-8% of the total WBC and are large cells with slightly lobed nuclei. Lymphocytes constitute about 20-25% of the total WBC and are smaller than monocytes.
Monocytes are phagocytic and also give rise to phagocytic cells called dendritic cells and macrophages. Lymphocytes do not phagocytize directly. They are involved in the adaptive immune response of the body.
J. wondered why the two agranulocytes were different in function. The facts of hematopoiesis which would help her are that monocytes develop from myeloid stem cells while lymphocytes develop from lymphoid stem cells. The word agranulocyte is used to indicate that these cells do not possess any kind of granules in the cytoplasm.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 5M1
The term “dendritic cells” matches with the phrase “first line of defense.” The first line of defense consists of skin, mucous membranes, lacrimal apparatus, normal microbiota and others like antimicrobial peptides.
Dendritic cells are present in the epidermal layer of the skin. These are phagocytic cells which are formed by monocytes. Dendritic cells have slender processes which extend among cells. These slender processes form a continuous network which traps pathogens.
These cells are nonspecific for pathogens and form the first line of defense. Dendritic cells also play a role in adaptive immunity.
Hence, the correct option is A. first line of defense.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 5M2
The term “cell from sebaceous gland” matches with the phrase “secretes sebum.” The secretion of sebum is the first line of defense of the body.
The skin contains sebaceous glands which secrete a substance called sebum. Sebum is an oily substance which keeps the skin oily and smooth. The sebum contains fatty acids which keep the pH of the skin at 5.5. This pH is not suitable for the growth of many microbes.
Along with sebaceous glands, the skin also contains sweat glands which secrete antimicrobial peptides and salt. These secretions also form the first line of defense along with sebum secretions.
Hence, the correct option is C. secretes sebum.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 5MC

The multiplication of viruses is not related to the complement system. When a virus or a bacterium enters the body, it is recognized as a foreign particle. After going through the complement pathway, the virus and the cell in which it is multiplying are both destroyed. Hence, the option (a) is incorrect.
Interferons are molecules, which are produced by viral infected cells. These molecules serve to warn the surrounding cells and protect them from viral invasion. The presence of complement is not needed for the synthesis and release of interferon. Hence, the option (b) is incorrect.
If the complement system is not inactivated, the process of protein synthesis would not be inhibited. Since the complement system is not needed for the synthesis of protein in the cell, protein synthesis is not hindered in any way. Hence, the option (c) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 5MTF
The given statement “Lymphocytes are large agranulocytes” is false. Lymphocytes are the smallest leukocytes in the blood while monocytes are the largest leukocytes. The nuclei in lymphocytes almost fill the whole cell, while the nuclei in monocytes are distinct and slightly lobed. Monocytes are a member of the white blood cells in the blood.
Monocytes are immature macrophages as they mature into macrophages after they leave the blood. They are also a part of the innate immune system. When monocytes mature, they give rise to macrophages and dendritic cells. Both the macrophages and dendritic cells play an important role in the innate immune response of the body.
The agranulocytes consist of lymphocytes and monocytes while the granulocytes consist of basophils, eosinophils and neutrophils.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 5SA
The classical complement cascade pathway from C1 to the MAC can be described in the following way:
The classical pathway is activated by the presence of Antigen-antibody complexes. The C1 protein is present in the serum and has high affinity for Antigen-antibody complexes.
When the C1 protein encounters an Antigen-antibody complex, it binds to it and a conformational change occurs in C1. Then proteolytic cleavage occurs in C1 which cleaves all the four polypeptide chains.
Two subunits of C1 then cleave the C4 protein into C4a and C4b. The fragment of C4a is released while the fragment of C4b binds to the Antigen-antibody complex-C1. The fragment C4b binds to C2 and the binding stimulates C1 to cleave C2 into C2a and C2b.
The C2b fragment is released while the C2a fragment binds to the complex of Antigen-antibody complex-C1-C4b.
This complex is known as C3 convertase. This helps to cleave the C3 protein into C3a and C3b. The fragment of C3a is released and induces inflammation. The fragment of C3b attaches to the complex to form the C5 convertase.
The C5 convertase cleaves C5 into C5a and C5b. The fragment of C5b then attaches to the complex while the fragment of C5a is released causing inflammation.
The other proteins of C6, C7, C8, and C9 then attach to C5b while the other fragments dissociate. The membrane attack complex is then formed which leads to lysis of the microbial cell.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 6CT
A patient is not able to produce the serum proteins C8 and C9. These two serum proteins play a vital role in the complement cascade system. These two proteins are needed for the formation of the membrane attack complex.
If the patient is not able to synthesize C8 and C9 proteins, he cannot fight infections by Gram negative and Gram positive bacteria. Hence, the infections by these bacteria would go unchecked even in the presence of the other serum proteins of the complement system. Only the inflammatory response by C3 proteins would be seen.
If the C3 and C5 fragments were also inactivated, this would lead to a total collapse of the complement cascade.
The activation of C3 produces the effects of opsonization and inflammation. This leads to the formation of C5 convertase which produces the effect of inflammation. All these effects are absent if C3 is missing. The absence of C5 leads to the absence of the C5 convertase complex. But the formation of the membrane attack complex does not occur.
The absence of the membrane attack complex leads to loss of function of the complement system.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 6M1
The term “alpha interferon” matches with the phrase “second line of defense.”
Interferons are protein molecules secreted by cells which have been attacked by viruses. The different types of interferons are:

Alpha
Beta
gamma

The source of these alpha interferons is the epithelium along with leucocytes. This type of interferon stimulates the production antiviral proteins. These interferons are seen early in the infection as the inducing agent is the virus. These interferons are not present late in an infection.
Beta interferons are also like alpha interferons. They also trigger antiviral proteins and are released within hours of infection by viruses. Gamma interferons are produced late in the infection. They are produced some days after the infection by viruses. These interferons activate macrophages and neutrophils which phagocytize the pathogens.
Hence, the correct option is B. second line of defense.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 6M2
The term “bone marrow stem cell” matches with the phrase “develops into formed elements of blood.”
The stem cells in the bone marrow have the capability of forming any kind of cell. The stem cells present in the bone marrow produce three types of cells:

Erythrocytes
Platelets
Leukocytes

Erythrocytes are the red blood cells which carry oxygen and carbon dioxide. Platelets are the cells involved in the process of blood clotting. Leukocytes are the white blood cells which are mainly used in defense of the body.
The leukocytes are further divided into granulocytes and agranulocytes. All these cells are called the formed elements of the blood. Hence, the correct option is H. develops into formed elements of blood.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 6MC
The source of the beta interferons is the fibroblast. These interferons are also stimulated by the presence of viruses just like alpha interferon. These molecules induce the formation of antiviral proteins. These interferons are not present late in an infection. Hence, the option (b) is incorrect.
The interferon delta was discovered in pigs. These molecules are produced by the trophoblast during implantation. This interferon is not involved in the immune response like other interferons. It is produced during the process of implantation of the egg in the uterus. Hence, the option (d) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 6MTF
The given statement “Phagocytes exhibit chemotaxis towards a pathogen” is true. Phagocytes are cells, which take part in the process of phagocytosis. They engulf pathogens and any other foreign material.
In the process of chemotaxis, a cell moves towards (or) away from the stimulus. If the cell moves towards the stimulus, it is called positive chemotaxis. If the cell moves away from the stimulus, it is called negative chemotaxis.
In phagocytes, positive chemotaxis is seen when the phagocytes produce pseudopodia and crawls towards the microbes at the site of infection. The microbial components and secretions act as chemotactic factors, along with the damaged tissues and cells of the host.
Leukocytes which are already present at the site of infection also release chemokines which also serve to attract phagocytic cells towards the microbial cells.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 6SA
The comparison between NOD proteins and Toll-like receptors are shown below:
microbiology-with-diseases-by-taxonomy-chapter-15-answers-6sa
So, the only difference between NOD proteins and Toll-like receptors is the location. Toll-like receptors are present on the surface of cells while NOD proteins are present inside the cell, in the cytosol.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 7CT
The sweat glands in the armpits secrete perspiration which has a pH close to 7.0. Since, this is a neutral pH; there should be no body odor. But, the armpits have more body odor than most parts of the skin.
The sweat secreted by the sweat glands has no smell at all. But, the location of the armpit is a closed area with not free passage of air. Because of this closed location, the perspiration does not have a chance to evaporate.
The persistence of sweat causes the occurrence of heat in the armpits. The combination of sweat and heat allow bacteria to multiply rapidly. These bacteria then break down the sweat into other compounds. These compounds are responsible for the body odor.
The other parts of the skin have some flow of air to evaporate the sweat. This does not allow sweat to remain for long on the skin. Hence, bacteria do not have the opportunity to break down the sweat molecules to cause a bad smell.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 7M1
The term “mucous membrane of the digestive tract” matches with the phrase “first line of defense.”
Mucus secreting membranes are found in the urinary system, respiratory passages, and digestive cavity. The membranes consist of tightly packed cells which are replaced frequently.
The digestive cavity is lined by mucus membranes. Since mucus membranes are an easy portal for microbes, the topmost cells are continually shed. This removes the organisms attached to the topmost layer of the mucus membranes. Dendritic cells are present below the mucus epithelium and phagocytize pathogens.
Goblet cells are also present amidst the cells of the mucous membrane. These cells secrete sticky mucous which helps to trap pathogens. Hence, the correct option is A. first line of defense.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 7M2
The term “Eosinophil” matches with the phrase “leukocyte that primarily attacks parasitic worms.”
Eosinophils are granulocytes which are a type of leukocytes. These cells attack pathogens in a non-phagocytic manner. They secrete anti-microbial chemicals. Eosinophils usually attack during parasitic infections. These cells attach to the surface of the worms and secrete extracellular toxins.
These extracellular toxins harm the outer surface of the worms and finally kill it. A high level of eosinophils in the blood is an indication of a worm infestation. The eosinophils can also use mitochondrial DNA as a means of killing bacteria.
Hence, the correct option is A. leukocyte that primarily attacks parasitic worms.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 7MC
Interferons do not protect the cell that secretes them; stimulate the activity of macrophages, and cause muscle aches, chills, and fever.

Interferons do not protect the cell that secretes them. Interferons are produced in a cell after viral invasion or infection has occurred. The interferons produced serve to protect the surrounding cells from viral infection. It cannot protect the cell that secretes them. Hence, the option (a) is correct.
Interferons stimulate the activity of macrophages. These macrophages are needed to recognize and eliminate the newly released viruses from the viral infected cell. These macrophages cannot protect the infected cells but can remove the viruses. If these macrophages were not stimulated, the viruses might infect other cells. Hence, the option (b) is correct.
The interferons produced by one cell can protect the surrounding cells from viral infection. But, as seen in viral infections, the side effects of interferons are muscle aches, chills, and fever. These symptoms are seen when interferons are produced. Hence, the option (c) is correct.
The term “all of the above” indicates that all the other given options are correct. Since, all the above conditions are correct and are related to interferons, we can say that all the above options are correct. Hence, the correct option is (d) all of the above.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 7MTF
The given statement “In phagocytosis, adherence involves the binding between complementary chemicals on a phagocyte and on the membrane of a body cell” is false. Adherence occurs between the phagocyte and the pathogen but not the body cell.
The process of phagocytosis occurs with the help of cells called phagocytes. These phagocytes engulf the microbial cell and destroy it. In the process of phagocytosis, we see six steps:

Chemotaxis
Adherence
Ingestion
Maturation
Killing
Elimination

Microbiology with Diseases by Taxonomy Chapter 15 Answers 8CT
Scientists can raise “germ-free” animals in the laboratories. These animals are usually raised in axenic environments. An axenic environment is one in which only one species exists.
Such animals would not be as healthy as their worldly counterparts. Since these lab animals are germ-free they will not have the immunity seen in their worldly counterparts. Such animals would be more susceptible to infection and their immune system is not very well developed.
The immune system of an individual usually develops by exposure to microbes. When individuals are raised in a germ-free environment, their immune system does not have a chance to develop. This makes their immune system weak.
Hence, the worldly animals will be healthier than the animals brought up under axenic environments in the laboratory.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 8M1
The term “neutrophils” matches with the phrase “second line of defense.” The second line of defense consists of cells like neutrophils, antimicrobial chemicals, and processes.
Neutrophils come under the category of leukocytes with granules. They are also known as polymorphonuclear leukocytes. Neutrophils are phagocytes which can phagocytize pathogens. These cells are present in the blood and move into the tissues through the process of diapedesis.
Another method in which neutrophils help to kill pathogens is through the formation of NETs. The term NET stands for neutrophils extracellular traps. These NETs are synthesized by neutrophils which involves the disintegration of their nuclei. The components of the nucleus mix with the components of the cytoplasm. This mixing forms NET fibers.
Superoxide and peroxide ions then kill the neutrophil. The NET formed in the cytoplasm of the neutrophil is released when the cell dies. These NETs trap Gram positive and negative bacteria along with antimicrobial peptides. These antimicrobial peptides then kill the bacteria. Hence, the correct option is B. second line of defense.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 8M2
The term “alveolar macrophage” matches with the phrase “phagocytic cell in lungs.” Alveolar macrophages are present in the lungs. These are not wandering macrophages but fixed in the same tissue.
Macrophages come under the second line of defense. These cells mainly take part in the process of phagocytosis. These are non specific cells and can phagocytize any foreign particle. The phagocytic cells in the brain and spinal cord are called microglia. The phagocytic cells present in the epidermal layer of the skin are called dendritic cells.
In the process of phagocytosis, we see 6 steps:

Chemotaxis
Adherence
Ingestion
Maturation
Killing
Elimination

At the end of phagocytosis, the pathogen is killed and the remnants thrown out of the cell.
Hence, the correct option is B. phagocytic cell in lungs.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 8MC
Single stranded RNA (ribonucleic acid) molecules are seen in viruses and some other pathogens. They are not seen in eukaryotic cells. So, the Toll-like receptors recognize these RNA molecules as foreign and trigger an immune response against them. These RNA molecules are then destroyed by the host immune system. Hence, the option (c) is incorrect.
The molecules of Lipoteichoic acid is usually seen in Gram negative bacterial cells. Since bacterial cells are pathogens, the Toll-like receptors recognize them and trigger the immune responses of the body. The Toll-like receptors are membrane proteins, which are produced by phagocytic cells. Hence, the option is (d) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 8MTF
The given statement “Opsonization occurs when a phagocyte’s pseudopodia surround a microbe and fuse to form a sac” is false. The process of ingestion occurs when the pseudopodia of a phagocyte surround the microbe and engulf it.
The process of phagocytosis occurs with the help of cells called phagocytes. In the process of phagocytosis, we see six steps:

Chemotaxis:
In the step of chemotaxis, the phagocyte is attracted towards the microbe.
Adherence:
In the step of adherence, the phagocytic cell binds to chemicals on the surface of the microbe.
Ingestion:
In the step of ingestion, the microbe is engulfed by the phagocyte by using pseudopodia.
Maturation:
In the step of maturation, fusion with a lysosome occurs.
Killing:
In the step of killing, the microbe is degraded by the enzymes in the lysosome.
Elimination:
In the step of elimination, the remnants of the digestion are eliminated by the process of exocytosis.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 9CT
The comparison of the protective structures and chemicals of the skin and mucous membranes is given below:
Skin:
Protective structures:

The epidermal layer also acts as a tough protective layer
Hair and hair follicles act as a protective structure
The multiple layers of the skin act as a physical barrier
Phagocytic dendritic cells are present which act as protective substances
The dermis of the skin contains collagen which also give protection

Chemicals of the skin:

Antimicrobial peptides are secreted by the dermal cells
Sweat glands secrete sweat which contains salt and lysozyme
Sebaceous glands secrete sebum

Mucous membranes:
Protective structures:

Mucous membranes have a connective tissue layer which provides support
Dendritic cells are present which give protection to the mucous membranes
Some mucous membranes possess goblet cells which secrete mucus
Some cells have cilia which help to trap and push out pathogens

Chemicals of the mucous membrane:

The mucous in the nose contains lysozyme
The mucous also contains antimicrobial peptides

Microbiology with Diseases by Taxonomy Chapter 15 Answers 9M1
The term “epidermis” matches with the phrase “first line of defense.” The first line of defense consists of skin, mucous membranes, lacrimal apparatus, normal microbiota and others like antimicrobial peptides.
The outer layer of the skin, the epidermis consists of dead cells. The epidermis consists of multiple layers of cells which are tightly packed. The topmost layer consists of cells which are dead and dry. These cells are shed continuously which do not allow most microorganisms to settle on the skin.
Dendritic cells are present in the epidermal layer of the skin. These are phagocytic cells which are formed by monocytes. Dendritic cells have slender processes which extend among cells. These slender processes form a continuous network which traps pathogens. Hence, the correct option is A. first line of defense.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 9M2
The term “microglia” matches with the phrase “phagocytic cell in central nervous system.” These are the resident macrophages present in brain and spinal cord. These macrophages form the first line of defense.
Macrophages come under the second line of defense. These cells mainly take part in the process of phagocytosis. These are non specific cells and can phagocytize any foreign particle. The phagocytic cells present in the epidermal layer of the skin are called dendritic cells. The macrophages in the lungs are called alveolar macrophages.
Macrophages are formed from the cells called monocytes. When monocytes mature, they turn into macrophages and get settled in a specific tissue. Hence, the correct option is F. phagocytic cell in central nervous system.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 9MC
The TLRs do not cause phagocytic chemotaxis. These TLRs are present on the surface of phagocytic cells and induce the response of the innate immune system. TLRs bind only to the microbial proteins and polysaccharides present on the surface of the microbial cells. Hence, the option (c) is incorrect.
The TLRs do not directly cause the destruction of microbial cells. They bind to the components of the microbial cells and send a signal to the immune system. The immune system then responds and kills the microbes. TLRs bind only to the microbial proteins and polysaccharides present on the surface of the microbial cells. Hence, the option (d) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 9MTF
The given statement is false. The correct answer is that lysosomes fuse with phagosomes to form phagolysosomes.
Phagosomes fuse with lysosomes in the process of phagocytosis. The exact step, where a lysosome fuses with a phagosome is called the maturation stage. In this stage, the phagosome containing the engulfed microbe fuses with a lysosome.
The fused product is known as phagolysosome. These phagolysosomes contain highly toxic forms of oxygen. They also contain antimicrobial substances in a pH of 5.5. In addition, there are about 30 different enzymes like proteases, nucleases, and lipases to destroy microbes.
After the death of the microbe, a phagolysosome is known as a residual body.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 10CT
Scientists are trying to develop antimicrobial drugs which behave like the antimicrobial peptides of the body.
Antimicrobial peptides are chains of amino acids which are positively charged. These peptides act against microbes. Since these peptides are found in many organisms apart from humans, scientists want to develop peptides which would do the work of an antibiotic.
These peptides would be given as drugs instead of antibiotics. The advantages of such drugs over antibiotics can be given below:

The side effects of antibiotics would be reduced
The tissue damage done by antibiotics can be avoided
Drug resistance can be avoided
Can be easily eliminated from the body

Microbiology with Diseases by Taxonomy Chapter 15 Answers 10M1
The term “lysozyme” matches with the phrase “first line of defense.” The first line of defense consists of skin, mucous membranes, lacrimal apparatus, normal microbiota and others like antimicrobial peptides.
Lysozyme is an enzyme present in the dermis of the skin. Lysozyme is an enzyme which destroys the cell wall of bacteria. It breaks down the bonding between the building blocks of the cell wall. Cells without a cell wall are susceptible and are killed quite easily.
The mucous in the nasal epithelium also contains lysozyme. The enzyme is present as the first line of defense to lyse any pathogens which enter the nose. Some microbes can be resistant to the action of lysozyme. Such microbes are usually a part of the normal flora. Hence, the correct option is A. first line of defense.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 10M2
The term “wandering macrophage” matches with the phrase “intercellular scavenger.”
Macrophages come under the second line of defense. These cells mainly take part in the process of phagocytosis. These are non specific cells and can phagocytize any foreign particle.
Wandering macrophages are those cells which are in the blood and move out of the blood whenever needed. These cells use the process of diapedesis and move out of the blood vessel and into the tissues when tissue damage occurs.
The macrophages in the blood are wandering macrophages while those in the tissues are fixed macrophages. The fixed macrophages in each tissue have different names according to the location. Wandering macrophages perform the role of scavenger intercellularly and extracellularly. Hence, the correct option is I. intercellular scavenger.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 10MC

The protein lactoferrin is a member of the transferrin proteins. It transfers iron molecules into the cells and controls the levels of free iron in the blood. Apart from this function, it also has antibacterial and antiviral activities. Hence, the option (a) is correct.
Siderophores are compounds, which bind to iron with high affinity. These siderophores are secreted by microbes like bacteria and fungi. Siderophores can also chelate other metals like aluminum, copper, lead, and manganese. Hence, the option (b) is correct.
Transferrins are glycoproteins, which are present in the plasma and bind to iron molecules. These molecules control the level of free iron just like lactoferrin. These molecules bind to iron very tightly but reversibly. Hence, the option (c) is correct.
Since the above three molecules can bind to iron, all the options are correct.Hence, the correct option is (d) all of the above.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 10MTF
The given statement “A membrane attack complex drills circular holes in a macrophage” is false. The membrane attack complex drills circular holes in the cytoplasmic membrane of a pathogen.
The membrane attack complex is seen in the process, where the complement system destroys microbes. The complement system is a set of serum proteins. These proteins act as chemotactic agents and trigger inflammation and fever in the host. The membrane attack complexes can be formed by 3 pathways.
The three pathways are:

Classical pathway
Alternative pathway
Lectin pathway

The formation of the membrane attack complex is a common step in all the three pathways. When this complex forms, it causes the formation of holes in the cytoplasmic membrane of the pathogens.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 11M1
The term “goblet cells” matches with the phrase “first line of defense.” The first line of defense consists of skin, mucous membranes, lacrimal apparatus, normal microbiota and others like antimicrobial peptides.
Goblet cells are present amidst the cells of the mucous membrane. These cells secrete sticky mucous which helps to trap pathogens. The goblet cells are epithelial cells which secrete mucin. These cells are usually found amid the epithelial lining of the respiratory and the intestinal tracts. These cells are not macrophages or phagocytes.
In some locations, ciliated cells are present in addition to goblet cells. These cilia help to push out the pathogens trapped in the mucous. Hence, the correct option is A. first line of defense.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 11MTF
The given statement “Rubor, calor, swelling, and dolor are associated with fever” is false. The above symptoms of rubor, calor, swelling and dolor are associated with inflammation.
Rubor indicates redness, calor indicates local heat, and dolor indicates pain. Inflammation is a process of the second line of defense of the body. It is a nonspecific response to the damage of tissues. The damage in tissues can be due to a variety of reasons like heat, cuts, chemicals, and pathogens.
There are two types of inflammation:

Acute
Chronic

Acute inflammation is short lived and results in the removal of the cause of the inflammation. In chronic inflammation, damage in tissues occurs which can lead to the death of the tissues. Both acute and chronic inflammation show the same symptoms of redness, heat, pain and swelling.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 12M1
The term “phagocytes” matches with the phrase “second line of defense.” The second line of defense consists of cells like phagocytes, antimicrobial chemicals, and processes.
Phagocytes are cells which take part in the process of phagocytosis. In the process of phagocytosis, we see 6 steps:

Chemotaxis
Adherence
Ingestion
Maturation
Killing
Elimination

Microbiology with Diseases by Taxonomy Chapter 15 Answers 12MTF
The given statement “Acute and chronic inflammation exhibit similar signs and symptoms” is true.
There are two types of inflammation:

Acute
Chronic

Acute inflammation is short lived, and results in the removal of the cause of the inflammation. In chronic inflammation, damage in tissues occurs which can lead to the death of the tissues. Both acute and chronic inflammation shows the same symptoms of redness, heat, pain and swelling.
Redness is called Rubor, localized heat is called calor, and pain is known as dolor. Inflammation is a process of the second line of defense of the body. It is a nonspecific response to the damage of tissues.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 13M1
The term “sebum” matches with the phrase “first line of defense.” The first line of defense consists of skin, mucous membranes, lacrimal apparatus, normal microbiota and others like antimicrobial peptides.
The skin contains sebaceous glands which secrete a substance called sebum. Sebum is an oily substance which keeps the skin oily and smooth. The sebum contains fatty acids which keep the pH of the skin at 5.5. This pH is not suitable for the growth of many microbes.
Along with sebaceous glands, the skin also contains sweat glands which secrete antimicrobial peptides and salt. These secretions also form the first line of defense along with sebum secretions. Hence, the correct option is A. first line of defense.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 13MTF
The given statement “The hypothalamus of the brain controls body temperature” is true.
The hypothalamus is a part of the brain, which controls the temperature of the body. Fever is a symptom seen when the body temperature rises above 37 degrees centigrade. Fever has side effects like malaise, tiredness, and body aches.
Fever is usually caused due to pyrogens. These pyrogens are chemicals, which reset the thermostat in the hypothalamus to a higher temperature. Pyrogens can include toxins released from bacteria, cytoplasmic contents of bacterial cells released after lysis, and chemicals released by phagocytes.
The symptoms of fever remain as long as pyrogens are present. When the infection starts to come under control, the level of pyrogens reduces and the body temperature is slowly reset to normal.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 14M1
The term “T lymphocytes” matches with the phrase “third line of defense.” There are two types of lymphocytes and both the types are made in the bone marrow.
T cells or T lymphocytes migrate to the thymus from the bone marrow. Then these T cells mature. The other cells are called B cells or B lymphocytes. These cells migrate to the fetal liver or spleen. But B cells can mature in either the bone marrow or in the spleen.
After maturation, these cells move around the body and look for foreign bodies. The T lymphocytes play a part in the cell-mediated response while B cells play a part in the humoral response or production of antibodies.
The specialized cells formed are:

Killer T cells
Helper T cells
Suppressor T cells
Memory cells

Hence, the correct option is C. third line of defense.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 14MTF
The given statement “Defensins are phagocytic cells of the second line of defense” is false. The antimicrobial peptides are phagocytic cells of the second line of defense.
These antimicrobial peptides are found in mucous membranes, and are secreted on the skin. These peptides are the second line of defense, which acts against pathogens which dare to attach to the skin. The antigens on the surface of the microbes trigger the antimicrobial action of these peptides.
Some antimicrobial peptides are specific against Gram negative or Gram positive organisms. Some can act against any bacteria while some act against the other organisms like protozoa, and fungi.
The mode of action of these antimicrobial peptides differs from each peptide. Some make holes in the membranes of the pathogens, while others prevent signaling and enzymatic action.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 15M1
The term “Antimicrobial peptides” matches with the phrase “first line of defense.” The first line of defense consists of skin, mucous membranes, lacrimal apparatus, normal microbiota and others like antimicrobial peptides.
These antimicrobial peptides are found in mucous membranes and are secreted on the skin. These peptides are the first line of defense which acts against pathogens which dare to attach to the skin. The antigens on the surface of the microbes trigger the antimicrobial action of these peptides.
The mode of action of these antimicrobial peptides differs from each peptide. Some make holes in the membranes of the pathogens, while others prevent signaling and enzymatic action.Hence, the correct option is A. first line of defense.

Microbiology with Diseases by Taxonomy Chapter 15 Answers 15MTF
The given statement “NETs are webs produced by neutrophils to trap microbes” is true.
The term NET stands for “neutrophils extracellular traps.” These NETs are synthesized by neutrophils, which involves the disintegration of their nuclei. When the nuclei break down, the DNA and the histone proteins are released. The components of the nucleus mix with the components of the cytoplasm. This mixing forms NET fibers.
Superoxide and peroxide ions then kill the neutrophil. The NET formed in the cytoplasm of the neutrophil is released when the cell dies. These NETs trap Gram positive and negative bacteria along with antimicrobial peptides. These antimicrobial peptides then kill the bacteria. Thus, the neutrophils kill bacteria in a method which involves killing themselves.

Microbiology with Diseases by Taxonomy Chapter 14 Answers

May 26, 2018 by Raju

Microbiology with Diseases by Taxonomy Chapter 14 Answers

Microbiology with Diseases by Taxonomy Answers

Microbiology with Diseases by Taxonomy Chapter 14 Answers 1CM
The following terms are given in the question:

Airborne
Arthropods
Biological
Body
Contact transmission
Direct contact
Droplet transmission
Fomites
Foodborne
Indirect contact
Mechanical
Mosquito
Sneezing
Tick
Vector transmission
Vehicle transmission
Waterborne

The concept map for the transmission of diseases is given below:
microbiology-with-diseases-by-taxonomy-chapter-14-answers-1cm

Microbiology with Diseases by Taxonomy Chapter 14 Answers 1CT
A menopausal woman, Mrs. E might have developed gingivitis from normal microbiota.
The onset of menopause might show some symptoms in some women. Some of the symptoms include:

Hot flashes
Night sweats
Irregular menses
Increased stress
Forgetfulness
Mood changes
Osteoporosis

Due to the above symptoms, the immune system of Mrs. E might have weakened. This might have caused the normal flora of the mouth to turn into opportunistic pathogens.
When these normal flora turn into pathogens, they cause diseases only in the persons with low immunity. In healthy normal individuals, normal flora does no harm to the host.
In the case of Mrs. E, it might be due to the weakened body, which allowed this normal flora to infect her.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 1FB
A microbe that causes disease is called a pathogen.
There are different types of microbes. The different groups are given below:

Those that live in a relationship with other organisms
Normal flora
Opportunistic pathogens
Disease causing microbes

Those that live in a relationship with others:
The relationships of mutualism, parasitism, and commensalism come under this category. In mutualism, both the organisms will be benefited, whereas in parasitism, only one organism gets benefit while the other is harmed. In commensalism, one organism will get benefit while the other is unharmed.
Normal flora:
The normal flora are the organisms, which are always present on our body. They do not cause any harm and protect the body from pathogens. Some microbes also synthesize vitamin K, which is used by the human body.
Opportunistic pathogens:
Some normal flora become opportunistic pathogens when the immunity of the host becomes low. These microbes use the opportunity and cause infection or disease.
Disease causing microbes:
Disease causing microbes are called pathogens. Their nature is to always infect and destroy host cells. Such microbes are usually highly virulent and cause disease in some host or the other.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 1L

The first diagram shows that the disease is endemic. Since the cases are spread far and wide, it can also be termed as sporadic. A disease is said to be endemic when it occurs continually for a specific population or in a specific area.
The second diagram shows that the disease is epidemic. Since the cases are concentrated in one area, it is an epidemic. In epidemic a disease occurs at a greater frequency than expected in a specific area or population.
The third diagram shows that the disease is pandemic. Since the cases are concentrated in different parts of the hemisphere and are seen in many parts of the hemisphere, it is called a pandemic.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 1MC

An interaction in which both members benefit is known as mutualism. Termites, which eat wood, cannot digest the cellulose in the wood without the presence of specific protozoa and bacteria in their bodies. The termites provide a home and food to the bacteria while the bacteria share the nutrients obtained from the wood with the termites. Hence, the correct option is (a) mutualism.
An interaction in which one partner gains the benefit while the other partner is harmed or injured is known as parasitism. In some cases, the host is killed. An example would be Tuberculosis bacilli in the lungs of humans. The bacilli are benefitted as they gain nutrients and reproduce. But, the human hosts are harmed as their respiratory system is damaged due to the presence of the bacilli. Hence, the option is (b) is incorrect.
Commensalism is a type of interaction, one partner benefits while the other partner is not affected at all. An example would be the presence of Staphylococci on our skin. The bacteria benefit by absorbing nutrients and growing on the skin of humans. The humans are not affected by this interaction. Hence, the option is (c) is incorrect.
Pathogenesis is not a type of interaction at all. Pathogenesis is the method of infection a parasite uses. If the lifecycle of the parasite takes place in the host, this also comes under pathogenesis. All the activities of the parasite from entry to exit from the host come under pathogenesis. Hence, the option is (d) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 1SA
The three types of symbiotic relationships are given below with an example for each:
Mutualism:
An interaction in which both members benefit is known as mutualism. Termites, which eat wood, cannot digest the cellulose in the wood without the presence of specific protozoa and bacteria in their guts. The termites provide a home and food to the bacteria while the bacteria share the nutrients obtained from the wood with the termites.
Parasitism:
An interaction in which one partner gains benefit while the other partner is harmed or injured is known as parasitism. In some cases, the host is killed. An example would be Tuberculosis bacilli in the lungs of humans. The bacilli are benefited as they gain nutrients and reproduce. But, the human hosts are harmed as their respiratory system is damaged due to the presence of the bacilli.
Commensalism:
In this type of interaction, one partner benefits while the other partner is not affected at all. An example would be the presence of Staphylococci on our skin. The bacteria benefits by absorbing nutrients and growing on the skin of humans. The humans are not affected by this interaction.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 2CT
Mr. W died of an E. coli infection after his intestine has punctured. This microbe usually lives in the intestine where it causes no harm.
Microbial flora are those organisms, which permanently live in specific sites in our body. These microbes usually do not cause any harm to the host. They maintain a commensal relationship with the host and leave the host unharmed. When these microbial flora are inserted into another site apart from the usual site, they can cause disease.
In the above case, the intestinal puncture in Mr. W resulted in the bacteria of the intestine spilling out. Since E. coli is usually present in colon, once it leaves the colon, it functions as a pathogen rather than a normal commensal.
So, the intestinal puncture enabled the E. coli from the colon to spread to other parts of the body and cause infection. Thus, Mr. W died of an E. coli infection.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 2FB
Infections that may go unnoticed due to the absence of symptoms are called asymptomatic or subclinical infections.
In some infections, there is an absence of symptoms. This does not indicate that the person is healthy. A person who feels healthy can be correctly diagnosed, if the correct tests are performed. This infection in which there is a lack of outward symptoms is called an asymptomatic or subclinical infection.
In infections like leukocytosis, the person does not have any symptoms. But, if the blood of the person is tested correctly, the diagnosis will show the disease. In diseases like AIDS, a long period occurs without any symptoms.
The people who are asymptomatic can also spread diseases. When a person is asymptomatic, the person can transfer bacteria without knowing. In the example of Typhoid Mary, she was asymptomatic, but spread the disease of typhoid to many people around her. When she was tested, she was found to be positive, but asymptomatic.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 2MC

An axenic environment is an environment that contains only one species. If there are many species of bacteria or microorganisms it is not called an axenic environment. Hence, the correct option is (b) contains only one species.
An axenic environment does not exist in the human mouth. An axenic environment is an environment that contains only one species. Since there many species of bacteria present in the mouth, it does not possess an axenic environment. Hence, the option (a) is incorrect.
An axenic environment does not exist in the human colon. Since there are about 106 million bacteria in the human colon and of different species, the human colon does not contain an axenic environment. Hence, the option (c) is incorrect.
The option of (a) and (c) cannot be right. The two options are mouth and human colon. Both these places have a large variety of bacteria. In the human colon, even the number of bacteria is very high. Since both these places possess a large variety of bacteria, the option (d) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 2SA
The three conditions that create opportunities for pathogens to cause disease in humans are:

Introduction of a species of normal flora into an unusual site in the body:
Normal flora are the species of microbes present in different parts of the body. Each part of the body has its own special flora.
Immune suppression:
Some conditions suppress the immune system. Conditions like disease, malnutrition, old or young, physical stress, emotional tensions, chemotherapy patients, radiation patients, usage of immunosuppressants in AIDS (Acquired immuno deficiency syndrome) patients and patients with a transplant can all face the problem of immune suppression.
Changes in the normal microbiota:
When changes occur in the microbial flora in a specific part of the body, it also gives a chance for a specific species to become an opportunistic pathogen. When women take antibacterial drugs for any other infection, the bacterial species in the vagina is also wiped out. This enables a species of yeast to proliferate. This causes an yeast infection.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 3CT
In the graph, we could see the epidemic of two diseases, which affect the patient for only one day. Neither the blue disease nor the red disease is treatable and doesn’t need treatment. In the graph, we see that both the epidemics begin at the same time.
The epidemic, which affected more people during the first 3 days is the red epidemic. The curve of the red line goes high into the graph which indicates that many people were affected by the red epidemic. In contrast, we see that the blue epidemic does not rise high in the graph like the red epidemic.
The short time course is seen in the red epidemic. We see that in 5 days, the red epidemic subsides. But, in the case of the blue epidemic, we see that it continues for 12 days. This difference in the course of the disease might be due to the short incubation period of the red epidemic.
When the incubation period of a disease is less, the other stages like prodromal period, illness, decline, and convalescence follow quickly. The incubation period of the red epidemic might be shorter than the incubation period of the blue epidemic. This would enable the red epidemic to affect more people in a short span of time.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 3FB
The study of the cause of a disease is etiology.
It is important to find out the cause of a disease because all diseases are not caused by infections. The different causes of diseases are:

Hereditary:
Some diseases are transferred from mother to child in the process of vertical transmission. These diseases are transferred through genes. They are passed from one generation to another.
Congenital:
These diseases are acquired at the time of birth. They can be due to genetic or environmental causes. They also can be defects during the process of development of the baby.
Degenerative:
These diseases are seen in the aged where it is a sign of slow degeneration. These diseases arise due to the wearing out of tissues and bones.
Nutritional:
Some diseases may arise due to nutritional deficiencies. Some maybe vitamin deficiencies like rickets, kwashiorkor. This usually happens when the vitamins are deficient in diet.
Endocrine/hormonal:
These diseases arise due to either less or too much secretion of the hormones of the body. In the example of thyroid hormones, the two types of hormonal imbalances are hyperthyroidism and hypothyroidism. Some of these defects can be rectified by taking supplements.
Mental:
These diseases can arise by mental tensions. The tension in the mind can give rise to rashes and other outward symptoms. Some other symptoms would be gastrointestinal distress and improper digestion.
Immunological:
These diseases can arise by the activity of the immune system. Sometimes, the immune system acts in a hyperactive way. These reactions are called hypersensitivity reactions. A few examples are Arthus reaction, hay fever, asthma and autoimmune diseases.
Neoplastic:
Any neoplastic growth can cause some kind of symptoms. As the tumor starts growing, it exerts pressure on the surrounding cells and tissues. Neoplastic growth can be benign or cancerous. Benign tumors usually grow slowly and do not cause much harm. Cancers, on the other hand can spread to other parts of the body.
Infectious:
These infections are caused by infection by pathogens. These pathogens usually infect and destroy host cells. Different pathogens cause different symptoms.
Iatrogenic:
These infections are physician induced infections. When a doctor uses instruments which are not properly sterilized, it allows the microbes to infect the patient. Since patients in hospitals have low immunity, microbes can easily infect them. Even things like cotton and gauze should be sterilized.
Idiopathic:
These diseases do not have any known cause. The symptoms do not have any known cause. Two examples would be Alzheimer’s disease and multiple sclerosis.
Nosocomial:
These diseases are those, which are acquired by health care workers. They can acquire these infections from the hospital surroundings or from patients themselves. One example would be Pseudomonas infection in a patient with burns.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 3MC
Out of the following statements, the explanation to show whether they are true or not is given below.

“Contaminants may become opportunistic pathogens.” The statement given in option (a) is true. Contamination by microbes is the mere presence of microorganisms on the surface. These contaminants include residents and temporary members. When the immunity of the individual becomes low or when the opportunity arises, these contaminants can become pathogens.
“Most microbial contaminants will eventually cause harm.” The statement given in option (b) is false. There are many microbes on the surface of our skin. These microbes do not harm us. Instead they protect us from pathogens which try to settle on our skin. Some microbes inside our body produce vitamin K, which is needed for our body.
“Contaminants may be a part of the transient microbiota.” The statement given in option (c) is true. The contaminant microbes might be a part of the microbiota present in or on our body. There are a large variety of microbes, which are present as normal flora in our body. Microbial contaminants can be a part of the normal flora.
“Contaminants may be introduced by a mosquito bite.” The statement given in option (d) is true. Yes, contaminants can be introduced by a mosquito bite. When a mosquito bites, it creates an opening in the skin. This small opening is enough for the contaminants of the skin to enter the wound. Hence, the false option is (b).

Microbiology with Diseases by Taxonomy Chapter 14 Answers 3SA
The three portals through which pathogens can enter the body are:

Skin:
The skin usually is a barrier to most microbes. But some microbes can use the natural openings of the skin like the hair follicles and the sweat glands. Other man-made openings like cuts, abrasions and wounds also serve as a portal of entry for microbes. Some species of fungi can digest the top layers of the skin and infect the body.
Mucous membranes:
This is the major portal of entry for microbes. There are many mucous membranes which are exposed to the outside environment. Some of them are respiratory, gastrointestinal, urinary, reproductive, and the conjunctiva. Since the mucous membranes are soft and living cells, it is easier to microbes to enter the body through this portal. Out of the different mucous membranes exposed to the outer atmosphere, the respiratory tract is the most used route for many microbes.
Placenta:
The placenta is the connection between the baby and the mother. It is useful in the exchange of wastes and nutrients between the baby and the mother. Most of the pathogens find the placenta a formidable barrier. But for some pathogens, the case is different. They can cross the placenta and infect the embryo.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 4CT
A young female of 27 years, consulted her doctor regarding symptoms of rash, fever, malaise, and muscle pain. She had also suffered from headache three days before these symptoms appeared. She also added that she had been bitten by a tick a week prior to the onset of the headache.
Her physician diagnosed Rocky Mountain spotted fever (RMSF) and gave her tetracycline. It took two days for the symptoms to subside, but she continued the antibiotic for 2 weeks.
The graph showing the course of the disease with the relative number of pathogens and the different stages of the disease is given below:
microbiology-with-diseases-by-taxonomy-chapter-14-answers-4ct

Microbiology with Diseases by Taxonomy Chapter 14 Answers 4FB
The study of where and when diseases occur and how they are transmitted within populations is epidemiology.
Epidemiology is the study where the pattern of a disease is studied along with the effect on the health of the general population. It also studies how the disease is transmitted from one person to another. The mode of infection of the disease is also studied.
Basing on the studies of epidemiology, preventive medicine can also be found. Necessary treatment is also needed for the patients. The risk factors like age or sex are also screened. The collection of all these types of data is needed.
The various types of data is collected and compared statistically. Even clinical trials come under the field of epidemiology. In such trails, a specific drug is given and the effect is observed in a group of people.
Sometimes, the course of the disease is studied. Some diseases like whooping cough have different and distinct stages. These can be identified and contagious patients can be separated.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 4MC

The respiratory tract is the most frequent portal of entry for microorganisms. The respiratory tract has some defenses like cilia and mucous production in the trachea and hair in nostrils. Despite all these defenses, microbes find easy to overcome these barriers and cause infections. The frequency of colds, coughs and other respiratory infections are much higher than the infections of other parts of the body. Hence, the correct option is (a) the respiratory tract.
The skin is the primary line of defense of the body. Microorganisms usually cannot penetrate the skin unless there are gashes and cuts. The skin has sebum secretions, which keep the skin waxy and prevent infections. In addition, the normal flora of the skin prevents pathogens from attacking the skin. Hence, the option (b) is incorrect.
The conjunctiva is present in the eye. The secretions frequently wash the eye and keep it sterile. The fluid in the eye prevents the growth of microbes. Since the conjunctiva is a mucous membrane with living cells, it can be a target for the entry of pathogens. Hence, the option (c) is incorrect.
A cut or wound is one of the methods by which pathogens can enter the body. When a cut or wound occurs in the skin, it gives the skin microorganisms a chance to enter the body. Since a cut or wound is an infrequent event, it is not the frequent portal of entry for microorganisms. Hence, the option (d) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 4SA
The four postulates of Koch are given below:

The suspected agent must be present in every case of the disease.
The agent must be isolated and grown in pure culture.
The cultured agent must be able to cause the same disease when it is inoculated into a healthy host.
The same agent must be reisolated from the same host which was injected with the agent.

The exceptions are:

Some microbes cannot be cultured in the laboratory. One example would be Mycobacterium leprae.
Some diseases are not caused by the pathogen alone. A combination of factors such as physical or genetic factors along with the pathogen is necessary for the disease.
For diseases which infect only humans, the third postulate cannot be followed. Humans cannot be purposely infected with pathogens.
Some conditions like hepatitis can be caused by many viruses. It would then be difficult to experiment with all the viruses.
Some pathogens were ignored at the time Koch’s postulates were given. Now, the real causes of some diseases are being discovered.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 5CT
After a visit to the local water park, over 30 children below the age of 3 developed gastroenteritis. The percentage of the sick children was about 44% of the total number of people who visited the park that day. Only children below 3 years were affected while older children and adults were unaffected. The causative agent was determined to be Shigella.
Based on the information given in the question, we can classify the outbreak as an epidemic. An epidemic is an infection or a disease, which occurs at a greater than normal frequency. Hence, the above situation is an epidemic.
As an epidemiologist, to determine which pools in the park are contaminated, I need to note down the data for each sick child and find out the pools visited by each person. The data would then be divided into the different age groups for better comparison.
The fact that no older children or adults developed the disease shows that the children had weak immune systems due to less age. People having extremes of age like very old people and very young kids have a weak immune system, which is not properly developed.
The park operators could frequently check the chlorine levels in all the pools to reduce the chances of future outbreaks of Shigella.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 5FB

Diseases that are naturally spread from their usual animal hosts to humans are called zoonoses.
Humans can acquire diseases like yellow fever, anthrax and rabies directly from animals. The animal usually acts as the reservoir. Sometimes, the animal is asymptomatic while sometimes the animal also suffers from the disease.
Zoonoses can also constitute viral, bacterial, fungal, protozoan, and helminthic diseases.
These microbes usually use animals as their reservoir host and get transferred to humans either through vectors or directly through animal bites.
Fecal contamination can also lead to zoonoses. Fungal infections like ringworm need to have direct contact for transmission to humans. They are transmitted from domestic animals to humans.
Viral infections like yellow fever are often spread by specific mosquitoes. The Hantavirus pulmonary syndrome is spread when the viruses in dried feces is inhaled. Worm infestations are usually through ingested larvae or eggs.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 5MC
Contamination is the presence of microbes on the surface of the object. Usually contamination objects do not cause infection but can become opportunistic pathogens. Contamination is not the process by which microorganisms attach to cells. Hence, the option (b) is incorrect.
The definition of disease is a condition in which the normal functioning of the body is hampered. Disease can be due to the infection by microorganisms, fungi or parasites. It is not the attachment of microorganisms to cells. Hence, the option (c) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 5SA
The five stages of infectious diseases in the correct sequence are:

Incubation period
Prodromal period
Illness
Decline
Convalescence

Incubation period:
The period between infection by the microbe and the appearance of first symptoms is called the incubation period. It will vary depending on many factors like:
- Virulence of the microbe
- Infective dose
- Health of the person
- Reproductive time period of microbe
- Site of infection
Prodromal period:
The period in which general symptoms are seen in the patient is known as prodromal period. The symptoms would be malaise, body aches, and weakness. This period is not seen in all illnesses.
Illness:
The most severe stage of the disease with all specific symptoms is known as illness. The full effect of the microbes is seen in the body. If any toxins are produced, the effect is usually seen during this period. This is the stage when a patient usually visits the doctor.
Decline:
In this period, the immune system of the patient slowly responds and begins to eliminate the microbes from the body. If any medical treatment is given, it also works to eliminate the microbes from the body. During this stage, the symptoms of the disease usually decrease. If the symptoms do not decrease, the disease is said to be fatal.
Convalescence:
During this period, the body of the patient returns to normal. The damages done by the microbes are slowly restored or repaired. The convalescent period varies from disease to disease. The length of the convalescent period depends on the amount of damage done, the nature of the microbe, the immune system of the patient and the site of infection.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 6CT
Lichen is a combination of a fungus and an alga, which grow together in a relationship of symbiosis. Each member gains from the relationship. The photosynthetic partner of the lichen is the alga, which has photosynthetic pigments. These photosynthetic pigments help it to perform photosynthesis.
The fungal partner provides the shelter for the alga. It also helps in retaining water and serves as a larger absorption area. The fungus surrounds the algal cells completely and sometimes the fungus penetrates the algal cell wall. This is similar to the haustoria seen in pathogenic fungi.
The algal partner reduces atmospheric carbon dioxide to organic compounds, which serves as food for both the partners. The fungus provides water and minerals to the algal partner, in addition to protection.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 6FB
Transmission of microbes through fomites is called indirect contact transmission. Normal infections like common cold and worm infestations can be easily transmitted through fomites. When a person with cold touches a chair, automatically transfers bacteria to the chair. The next person who touches the chair is likely to be infected. Even medical equipment in hospitals like dental equipment can be a source of microbes. They can easily transfer to patients. The bed sheets in hospitals can also be a source of infection if not washed properly. In the same way, the operation apron of the surgeons should be sterile.
Needles and blood products are very easy way of transmission. When contaminated needles are used and blood products are not checked for diseases, dangerous diseases like AIDS and Hepatitis can be transmitted. In houses, worm infestations can spread easily if not kept in check. The person suffering from worm infestations should be careful to infect others through fomites.
Nonliving reservoirs of disease, such as toothbrush, drinking glass, and needle, are called fomites.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 6MC
The first stage of infection is incubation. This stage is not followed by the stage of decline. The stage of decline occurs after the stage of illness. The correct sequence of events for an infectious disease is incubation, prodromal period, illness, decline and convalescence. Hence, the option (b) is incorrect.
The first stage of prodromal period is incorrect. The first stage of an infectious disease is always incubation. In the order given in this option, the first two options are interchanged. Hence, this option (c) is incorrect.
The first stage of convalescence is incorrect. The first stage of an infectious disease is always incubation. Hence, the option (d) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 6SA
The three modes of disease transmission are:

Contact transmission
Vehicle transmission
Vector transmission

Contact transmission:
There are three types of contact transmission:
- Direct contact:
  Direct contact involves touching and other activities between two persons. Sexual diseases are transmitted through sexual contact and skin diseases can be transmitted through hugging and other skin-to-skin contact. The transfer of microbes from mother to fetus through the placenta is another mode of direct transmission.
- Indirect contact:
  Indirect contact occurs through fomites. Fomites are non-living objects, which has been contaminated by the patient. When a healthy person uses or touches the same object, the pathogens get transferred to the healthy person. Objects like needles and syringes can also be used in the transfer of microbes.
- Droplet transmission:
  This type of transmission occurs through droplets. When a person sneezes, the droplets from the sneeze remain in the air for a long period of time. When a healthy person enters the same area and breathes that air, these pathogens then enter his body and cause disease. Only if the pathogens are transmitted for a distance of less than 1m, it is called droplet transmission.
Vehicle transmission:
There are four types of vehicular transmission:
- Airborne transmission:
  When pathogens from sneezing or coughing are transmitted over a distance of more than 1m, it is known as airborne transmission. If the distance is less than 1m, it comes under droplet transmission.
- Waterborne transmission:
  Some diseases are transmitted through water. When fecal contamination occurs, waterborne diseases occur. Large water bodies can also act as a reservoir for pathogens.
- Foodborne transmission:
  The transmission through foods is usually through undercooked or poorly refrigerated foods. Improperly pasteurized milk can also be a source of pathogens. Foods can also be contaminated with normal flora.
- Bodily fluid transmission:
  Blood, urine, and saliva are the usual body fluids in the transmission of pathogens. Health workers can be easily affected by body fluids if they are not careful. Some diseases like AIDS (Acquired immuno deficiency syndrome) are transmitted through blood. So, if the health worker has a slight injury in a hand and handles blood, there is a high risk of getting infected.
Vector transmission:
There are two types of vectors:
- Biological vectors:
  In some diseases, the vector not only carries the pathogen, but also serves as a host for the pathogen. Sometimes, a part of the lifecycle of the pathogen occurs in the vector. The usual sites of replication within a vector are the salivary glands and the gut.
- Mechanical vectors:
  These vectors only act as carriers. They do not act as hosts for the pathogens. The pathogens are usually carried on the feet or other body parts. A good example would be the housefly which carries pathogens from the dustbin to the kitchen.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 7CT
In the clinical case study of the Legionnaires’ disease, the facts are given below:

33 cases of the disease in the town
Total population is 16,000
It is a potentially fatal disease
All victims had shopped at the same grocery store
The vegetable misting machine was the source of the bacteria

The incidence of this Legionnaires’ disease can be calculated in the following way:
microbiology-with-diseases-by-taxonomy-chapter-14-answers-7ct
The incidence rate is 2.06 per 1000 people.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 7FB
There are three types of nosocomial infections:
Exogenous:
The infections are acquired from outer environment. They can be due to working with infectious patients or handling their clothes. Even patients with low immunity levels can be infected with microbes in a hospital setting.
Endogenous:
The endogenous infections are also called as nosocomial infections, but arise from the patient himself. Normal floras, which are present all over the body, can turn into pathogens when the immunity of the individual is lowered.
Iatrogenic:
The infections are known as physician induced infections. The instruments used by the physician can serve as fomites. Even medical equipment in hospitals like dental equipment can be a source of microbes. They can easily be transferred to patients.
Thus, nosocomial infections are acquired by patients or staff in health care facilities.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 7MC

The pathogens which are highly virulent are the most likely to cause disease in hosts. These pathogens easily pass the defenses of the body and cause infection. Since they are without any defective or absent enzymes, they are the most likely to cause disease. Hence, the correct option is (d) highly virulent organisms.
The normal flora of the body can become opportunistic pathogens. The normal flora is usually present in almost all parts of the body and does no harm. But when the immunity of the host becomes low, this normal flora can cause disease. But, it does not always occur. Hence, the option (a) is incorrect.
Those pathogens which lack the enzyme kinase cannot carry out many reactions of the cell. One example would be the process of signal transduction. This process needs the enzyme of kinase. Hence, it would be difficult for such pathogens to cause disease. Hence, the option (b) is incorrect.
Those pathogens which lack the enzyme collagenase cannot carry out some important reactions of the cell. The enzyme collagenase is required to lyse the protein collagen in host cells. When this important enzyme is missing, it would be difficult for such pathogens to cause disease. Hence, the option (c) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 7SA
The parenteral route of infection can be described in the following way:
The parenteral route of infection is not a portal of entry. Microorganisms cannot easily enter the body through this route. Pathogens can use this route only with the help of instruments or any other human means.
The parenteral route is the one used to give injections. So when injections are given, there is a chance of pathogens gaining entrance into the body through the puncture site. The gashes by a nail are also enough for pathogens to enter the body.
Other methods include being pricked by a thorn, cuts, bites, stab wounds, surgical wounds, and deep abrasions. All these are the means by which pathogens can use the parenteral route. In the absence of any of these methods, pathogens cannot enter the body through the parenteral route.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 8FB
The total number of cases of a disease in a given area is its prevalence.

The prevalence of a disease is tracked by epidemiologists. Prevalence is the total number of cases of that specific disease. The total number includes the new cases and the existing cases in a given area in a specific period of time.
Prevalence is usually stated as a percentage. It is given as the number of affected people out of the total population. It can also be given as number of cases per 10,000 or per 100,000 individuals.
Prevalence differs from incidence in that prevalence is the number of existing cases and the number of new cases, while incidence is the number of new cases. Prevalence is used to compare statistics over a long period of time.
The statistics taken 2 years ago can be compared with the statistics taken 5 years ago. This type of comparison helps us to know whether the disease regularly appears in a specific period or if it reduces over a long period of time. Hence, the correct answer is prevalence.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 8MC
The capsule enhances the virulence of a bacterium. Since the capsule helps the cell in attachment to host cells and also in evading the defense systems of the host, it helps to increase the virulence of the bacterial cell. The cilia and the mucous secretions in the respiratory tract of the host are easily bypassed when the bacterium possesses a capsule. Hence, the correct option is (c) affects the virulence of these bacteria.
The capsules present in bacteria do not cause clotting. They usually play a role in the virulence of bacteria. They help the bacterium in evading the defense mechanisms of the host. The nature of the capsules might be different in different bacteria. Hence, the option (a) is incorrect.
A capsule helps the bacterium to evade the phagocytic cells of the host. It does not allow phagocytes to engulf the bacterium. Some bacteria like Pneumococcus have a capsule, which helps them to easily attack the respiratory system of the host. Hence, the option (b) is incorrect.
The capsule of a bacterium does have a specific effect on the virulence of the bacterium. The presence of a capsule on the outer side of a bacterium helps it to evade the phagocytes of the immune system of the host. Thus, when encapsulated bacteria lose their capsules, they become avirulent. Hence, the option (d) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 8SA
Transient microbiota can be compared with resident microbiota in the following way:
microbiology-with-diseases-by-taxonomy-chapter-14-answers-8sa
Microbiota can consist of bacteria, fungi, and protozoa. These normal microbiota are usually acquired from the hospital environment and surrounding people after the birth of the child.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 9FB
An animal that carries a pathogen and also serves as host for the pathogen is a biological vector.
These vectors also serve as hosts for the pathogen they carry. The pathogen usually carries out a part of its lifecycle in the body of the vector. The example is malarial pathogen. The Anopheles mosquito also serves as a host and a part of the lifecycle is carried out in the mosquito.
Biological vectors are usually bugs, flies, mites, fleas, lice, ticks, mosquitoes, and blood-sucking arthropods. The usual site of replication within a vector is the salivary gland or the gut. The bite of the vector usually carries the pathogen, which is directly injected into the next host.
Biological vectors are different from mechanical vectors. When transmission occurs through mechanical vectors, the lifecycle of the pathogen does not occur in the vector. The vector simply carries the pathogen on their feet or wings. Hence, the correct answer is biological vector.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 9MC
Some bacterial cells can produce endotoxin when they die. These endotoxins are responsible for the adverse affects seen in the host. The endotoxins are not produced when the bacteria lose their ability to make adhesins. Adhesins are proteins required for the attachment of the bacterial cells to host cells and endotoxins are released when the bacterium dies. Hence, the option (b) is incorrect.
When bacterial cells are unable to produce adhesins, they do not absorb endotoxins. Endotoxins are the products released by bacterial cells when they die. These endotoxins are usually present in the cell wall of Gram negative bacteria. When bacterial cells are unable to produce adhesins, they become avirulent. Hence, the option (c) is incorrect.
When bacterial cells are unable to produce adhesins, their virulence is not increased. Instead of virulence increasing, the virulence decreases. Since adhesins are useful in attachment of bacteria to host cells, when adhesins are not produced, the bacteria can no longer attack the host cells. This leads to loss of virulence. Hence, the option (d) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 9SA
The terms “infection” and “morbidity” can be compared in the following way:
An infection is the term used when a pathogen successfully crosses all the barriers and defenses of the immune system and multiplies in the body. The multiplication of the pathogen may not cause any visible symptoms in the body. The infection might not lead to disease or appearance of any strange symptoms. The normal functioning of the body is also not affected.
The term morbidity is used differently when compared to infection. As in infection, a pathogen needs to cross the barriers of the immune system and establish itself in the body. It also multiplies in the body of the host. But, in this case it causes the appearance of symptoms in the host. The appearance of the specific symptoms leads to disease. In morbidity, the normal functioning of the body is affected and health is lost.
The terms infection and morbidity only differ slightly in that the presence of infection does not always indicate a disease; while in morbidity, the symptoms and presence of disease is seen.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 10FB
Endotoxin is the part of the cell wall known as lipid A in a Gram negative bacterium.
The endotoxin is the lipid part present in Gram negative bacteria. These endotoxins are released only under certain conditions. When the cell dies or divides or is digested by phagocytes, lipid A is released. There are different types of lipid A, which are present in different bacterial cells.
The symptoms of endotoxin poisoning are:

Fever
Inflammation
Shock
Blood coagulation
Hemorrhaging, and
diarrhea

The different types of diseases which are due to endotoxins are:

Typhoid fever
Tularemia
Endotoxic shock
Urinary tract infections
Meningococcal meningitis

Hence, the correct answer is lipid A.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 10MC
An acute disease is a disease in which the symptoms develop rapidly. The severity of the disease becomes very high quickly but the decline is also quite fast. The duration of the disease is short. In this disease, the pathogen does not remain inactive. Hence, the option (b) is incorrect.
A chronic disease is a disease in which the symptoms develop slowly. The severity of the disease slowly increases and the decline of the disease is also quite slow. The duration of the disease is quite long. In this disease, the pathogen does not remain inactive. Hence, the option (c) is incorrect.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 10SA
Iatrogenic and nosocomial diseases can be compared in the following way:
Iatrogenic diseases are a part of nosocomial diseases. Iatrogenic diseases are also known as physician-induced diseases. When a physician uses improperly sterilized instruments, the microbes present on the instrument are easily transferred to the patient. These diseases can also be due to medical procedures done inside the body with the help of instruments.
Nosocomial diseases are diseases, which are acquired in a hospital setting. These diseases are usually acquired by health workers who work in hospitals and health facilities. The environment of the hospital and contagious patients usually give nosocomial diseases. The three types of nosocomial diseases are endogenous, exogenous, and iatrogenic infections. Endogenous infections are those, which are due to the normal flora becoming opportunistic pathogens. Exogenous infections are those acquired from the environment of the health facility. Iatrogenic infections are those, which are physician induced and arise due to instruments or medical treatments.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 11MC
The best definition of a pandemic disease would be the statement:
“It is an epidemic that occurs on more than one continent at the same time.”
a) It normally occurs in a given geographic area:
A pandemic does not occur in a given geographic area. When a disease occurs in a given geographic area, it is called an endemic but not a pandemic. Hence, this option is incorrect.
b) It is a disease that occurs more frequently than usual for a geographical area or a group of people:
A pandemic is not a disease that occurs more frequently than usual in a specific group of people. When a disease occurs in such a way that the frequency of the disease is more than usual and only occurs in a specific group of people, it is called an epidemic but not a pandemic. Hence, this option is incorrect.
c) It occurs infrequently at no predictable time scattered over a large area or population:
A pandemic is not a disease that occurs infrequently over a large population. When a disease occurs at no predictable time and infrequently over a large area, it is called a sporadic disease but not a pandemic. Hence, this option is incorrect.
d) It is an epidemic that occurs on more than one continent at the same time:
A pandemic is an epidemic that occurs on more than one continent at the same time. When the same disease is seen in large numbers over many continents, it is called a pandemic. Hence, this option is correct. Hence, the correct option is (d) it is an epidemic that occurs on more than one continent at the same time.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 12MC
Out of the following given types of epidemiologists, the one who is like a detective is an analytical epidemiologist.
a) A descriptive epidemiologist:
A descriptive epidemiologist needs to carefully tabulate and note down the data in connection with a disease. The area of spread of disease along with the information of the patients is tabulated. The transmission of the disease is also noted. Since these epidemiologists need to just tabulate and compare cases, they cannot be like a detective. Hence, this option is incorrect.
b) An analytical epidemiologist:
An analytical epidemiologist is a person who investigates a disease. He also analyzes the cause, the mode of transmission and the prevention of the disease. Such a person analyses these details only after the outbreak has occurred. He also has to find out if there are any other factors like age and sex which influence the spread of the disease. Since, an analytical epidemiologist needs to analyze and investigate just like a detective, this option is correct.
c) An experimental epidemiologist:
An experimental epidemiologist usually uses a hypothesis to test the cause of a disease. These epidemiologists also involve studies and experiments to test out the hypothesis. They can experiment on humans or animals. These people need to test and check whether a specific drug can be used to treat the disease. They also need to test for the cause and prevention of the disease. Since, an experimental epidemiologist does not analyze but only experiments, he is not like a detective. Hence, this option is incorrect.
d) A reservoir epidemiologist:
A reservoir epidemiologist usually checks out for the reservoir host of the pathogen causing the disease. A pathogen usually multiplies in a reservoir host without causing any symptoms in the host. The pathogen is then transmitted either to the intermediate host or to the final host. Since, a reservoir epidemiologist does not need to analyze, he is not like a detective. Hence, this option is incorrect. Hence, the correct option is (b) an analytical epidemiologist.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 13MC
The details of a case are given below:
A virus has infected an animal. A mosquito bites the animal and gets contaminated by the virus. The mosquito then goes and bites a human being. The vector in this case is the mosquito.
a) Animal:
The animal cannot be the vector in this case. A vector is one which transfers the virus from one host to another. In the above case, the animal does not transfer the virus from one host to another. It is acting as the reservoir host in this case. Hence, this option is incorrect.
b) Virus:
The virus cannot be the vector in this case. The virus is the pathogen in this case. A vector is one which transfers the pathogen from one host to another. Since it is the virus which is getting transferred and not the one which transfers, it cannot be the vector. Hence, this option is incorrect.
c) Mosquito:
The mosquito is the vector in this case. It transfers the virus from the animal to the human being. In this case, the animal is the reservoir host while the human is the final host. The mosquito transfers the pathogen from the reservoir to the host. Hence, this option is correct.
d) Person:
The person cannot be the vector in this case. Since the person is the final host in this case, it cannot be the vector. Also, the human does not transfer the virus to any other human or organism. The human is at the receiving end of the chain and does not transfer the virus. Hence, this option is incorrect. Hence, the correct option is (c) mosquito.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 14MC
The details of the case are given below:
A patient contracted the disease of athlete’s foot after using a specific medicine for a long time. His doctor explained that the disease was directly due to the medication. Such diseases or infections are called as endogenous infections.
a) Nosocomial infections:
These infections are not due to long term use of medicines. When a health worker works in a hospital or health facility, he can acquire the infection from the hospital. He can acquire it from a patient or through fomites or through aerosols. Hence, this option is incorrect.
b) Exogenous infections:
These infections do not occur due to long term use of medicines. These infections are acquired from the environment of the hospital. These are usually acquired by hospital workers and helpers. These are one type of nosocomial infections. Hence, this option is incorrect.
c) Iatrogenic infections:
These infections are also called as physician induced infections. They can occur when doctors use improperly sterilized instruments or through catheters or any surgical equipment. These infections are usually acquired during surgery or any cleaning procedures in hospitals. They are not caused due to long term use of medicines. Hence, this option is incorrect.
d) Endogenous infections:
These infections are those which occur when the immunity of the person becomes low. Since the whole body is covered with normal flora, when immunity is lowered, these normal flora cause disease. In the above case, the long term use of medicine lowered the immunity of the person. The lowered immunity gave the normal flora the opportunity to become pathogens. Hence, this option is correct.
Hence, the correct option is (d) endogenous infections.

Microbiology with Diseases by Taxonomy Chapter 14 Answers 15MC
Out of the following given phrases, the best one which describes a contagious disease is “a disease that is easily passed from host to host in aerosols.”
a) A disease arising from fomites:
Fomites are non-living objects which can play a part in transfer of microbes. A good example would be the presence of cold-causing bacteria on the hands of the patient. When he holds a chair, he transfers these bacteria to the chair. When a normal person holds the same chair, he gets infected by these bacteria. In this way, the chair acts as a fomite in the transfer of microbes. Hence, this option is incorrect.
b) A disease that is easily passed from host to host in aerosols:
A disease which is passed through aerosols is called a contagious disease. A contagious disease can easily spread from one person to another. Some examples of contagious diseases are common cold and tuberculosis. Both these diseases spread through aerosols. When a person sneezes, the droplets from the sneeze remain in the air and can enter the respiratory tract of the next person who comes to that place. Hence, this option is correct.
c) A disease that arises from opportunistic, normal microbiota:
A disease that arises from normal microbiota is called an endogenous infection. Normal flora are the microbes which are present permanently on our body. These flora usually do not harm the body. But, when the immunity of the person becomes low, sometimes these normal flora becomes opportunistic pathogens. They cause disease. These diseases cannot be passed from one host to another through aerosols. Hence, this option is incorrect.
d) Both a and b:
The option of (a) is not correct. A disease arising from fomites is not contagious through aerosols. It is contagious but through fomites or non-living objects. The option of (b) is correct. But both these options cannot be correct. Hence, this option is incorrect. Hence, the correct option is (b) a disease that is easily passed from host to host through aerosols.

Microbiology with Diseases by Taxonomy Chapter 13 Answers

May 26, 2018 by Raju

Microbiology with Diseases by Taxonomy Chapter 13 Answers

Microbiology with Diseases by Taxonomy Answers

Microbiology with Diseases by Taxonomy Chapter 13 Answers 1CM
The following terms are used to prepare concept map:

+ssRNA
–ssRNA
Assembly
Attachment
Budding
dsDNA
dsRNA
Endocytosis
Entry
Exocytosis
Fusion
Host cells
Lysis
New virions
Release
ssDNA
Synthesis
Uncoating
Viral genome
Viral nucleic acid
Viral proteins

The concept map describes the replication of viruses is shown below:
microbiology-with-diseases-by-taxonomy-chapter-13-answers-1cm

Microbiology with Diseases by Taxonomy Chapter 13 Answers 1CT
Small viruses have single stranded genome and viruses in larger size have double stranded genome. The genome can be either DNA (deoxyribonucleic acid) or RNA (ribonucleic acid). The nature of the genome seems to be directly proportionate to the size of the virus. Moreover, small viruses usually do not need more proteins for synthesis of new viruses. Since, very few proteins are needed, the genome of the virus is small and single stranded. Larger viruses need more number of proteins and have a larger genome.
Additionally, family Circoviridae has smallest viral genome, which is single stranded and codes for only 2 proteins. The viruses, which are the larger, are Pandora viruses having double stranded DNA and code for about 2500 proteins.
Therefore, the stranded nature of the genome depends upon the proteins coded by the virus, which is related to the size of the virus.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 1L
The labeled diagram of the lytic replication cycle of the bacteriophage is shown below:
microbiology-with-diseases-by-taxonomy-chapter-13-answers-1l
The steps shown above are explained below:

Attachment:
The bacteriophage attaches to the cell membrane of the bacterial cell with the help of the tail fibers.
Entry:
Once the step of attachment is complete, the phage makes a small hole in the cell membrane of the host. The genome of the virus is then pushed inside the cell through this hole. The protein coat is left outside the cell.
Synthesis:
Once the genome of the virus enters the host bacterial cell, it orders the host machinery to start the synthesis of the daughter virions based on the code present in the viral genome.
Assembly:
The different components of the virus are synthesized separately and then fitted together. This step is called assembling of the virus or assembly.
Release:
After the completion of the synthesis of all the daughter virions, the host cell bursts to release the newly synthesized daughter virions into the surroundings.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 1M
The term “uncoating” matches with the phrase “removal of capsomeres from a virion.” Capsomeres are a unit of the protein capsid, which is present in a virus. This protein capsid encloses the genetic material of the virus. The genetic material of a virus can be either DNA (deoxyribonucleic acid) or RNA (ribonucleic acid).
The process of uncoating is the removal of the protein coat from the virus. This is usually seen when the virus infects a host cell. When the virus first begins to infect the host cell, it attaches to the cell with the help of the tail fibers. This step is called attachment.
After the step of attachment, comes the step of uncoating. The genome of the cell slips into the host cell, leaving the protein coat outside the cell. The coat is left attached to the cell membrane, while the genome enters the host cell. Hence, the correct phrase is H. removal of capsomeres from a virion.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 1MC
The following types of organisms are given.
a) Viroid
b) Virus
c) Rickettsia
d) Prion
Out of the following options, all are acellular agents except rickettsia.
a) Viroids are circular fragments of RNA (ribonucleic acid), which have no protein capsid. These viroids cause diseases in plants. Since viroids are not made up of cells, but only made of RNA particles; they are treated as acellular organisms. In addition, they cannot grow, reproduce, or have any metabolic reactions. Hence, option (a) is not the right answer.
b) Viruses are small agents with a nucleic acid of RNA (ribonucleic acid) or DNA (deoxyribonucleic acid) surrounded by a protein coat. Since viruses are not made of cells and only composed of nucleic acid and protein, they are also treated as acellular organisms. In addition, they cannot grow, self-reproduce, or have any metabolic reactions. Hence, option (b) is also not the right answer.
c) Rickettsia is a type of bacteria, which are gram negative, non-motile, and present as a coccus. Since they are bacteria, they have their own metabolizing machinery along with the ability to grow and reproduce unlike acellular agents like viruses and viroids. These organisms have their own DNA and protein and can also synthesize DNA, protein, and other biomolecules. Hence, option (c) is the right answer.
d) Prions are small protein particles, which have the ability to infect. They lack their own DNA, but can convert normal proteins into prions. The diseases caused by prions are usually transmitted by contaminated meat and affect the brain. These diseases are usually incurable. Since these molecules do not have their own DNA and cannot metabolize, they are acellular molecules. Hence, option (d) is not the right answer. Hence, the correct answer is option (c) Rickettsia.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 1SA
The comparison of a bacterium and a virus is given in the following table:
microbiology-with-diseases-by-taxonomy-chapter-13-answers-1sa
The explanation for the above aspects is given below:
Cell membrane:
A bacterial cell has a cell membrane which encloses all the components of the cell. The cell membrane also protects the cell from environmental factors. A virus does not have a cell membrane. A virus has a capsid to protect the genome of the virus. The other parts of the virus are not enclosed in any sort of membrane.
Functional ribosome:
A bacterial cell has functional ribosomes for the synthesis of protein. A ribosome is an organelle used in the process of protein synthesis. Without the ribosome, a cell cannot synthesize its own proteins. A virus does not have any functional ribosomes. Since the virus uses the machinery of the host for the synthesis of its own proteins, it does not need ribosomes.
Cytoplasm:
A bacterial cell has cytoplasm. Cytoplasm is the fluid-like substance present inside the cell of the bacterium. It also helps in the movement of substances from one part of the cell to another. A virus does not have cytoplasm.
Nucleic acid:
Both bacterial cells and viruses have nucleic acids as their genome. Bacterial cells usually have DNA (deoxyribonucleic acid) as their genome. Viruses can have either DNA or RNA (ribonucleic acid) as their genome. The genome in viruses can be either single stranded or double stranded.
Nuclear membrane:
The nuclear membrane is absent in both bacteria and viruses. Since bacteria are prokaryotes they possess a genome, but do not possess a nucleus or a nuclear membrane. In viruses also, the nuclear membrane is absent.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 2CT
The advantages and disadvantages of the lytic and lysogenic cycles of bacteriophage replication are given below:
Advantages:

In the lytic cycle, the release of all new virions at the same time is an advantage to bacteriophage, as surrounding cells can also be infected easily.
The lytic cycle is of short duration when compared to the lysogenic cycle.
In the lysogenic cycle, the viral genome can be transmitted to the daughters of the bacterial cell.
Protection from the environment occurs in the lysogenic cycle when the prophage remains latent.

Disadvantages:

Host is killed in lytic cycle, so the bacterial daughter cells cannot be infected by the virus.
Replication is longer in the lysogenic cycle.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 2M
The term “prophage” matches with the phrase “inactive virus within bacterial cell.” A virus can undergo either the lytic cycle or the lysogenic cycle after infection of the host cell. There are specific viruses, which undergo lysogeny.
In the lytic cycle, the viral genome forces the host genome to synthesize virions using the host machinery and enzymes. After synthesis of daughter virions, the host cell undergoes lysis or cell death to release the virions into the surrounding matrix. In this cycle, the prophage is not seen.
In the lysogenic cycle, the viral genome integrates with the host genome. It can stay latent and is called a prophage. This viral genome is replicated along with the host genome and can also be transferred to the daughter cells of the host. Sudden changes of environment or any stimulus can reactivate the prophage which will then continue the lytic cycle. Hence, the correct phrase is G. inactive virus within bacterial cell.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 2MC
Out of the given statements, the explanation to show whether they are true or not is given below.
a) “Viruses move towards their host cells.” This statement is false. Viruses usually do not have means of movement outside cells. They can move inside the body of cells with the help of body fluids. But, outside cells, they do not possess pseudopodia or flagella or cilia to help them in moving towards host cells.
b) “Viruses are capable of metabolism.” This statement is false. Since viruses are composed only of nucleic acid and protein, they cannot metabolize. They cannot break down organic molecules or synthesize their own DNA (deoxyribonucleic acid) or protein. They cannot grow or self-reproduce without the help of the host. They use the host enzymes and proteins to synthesize their own proteins.
c) “Viruses lack a cell membrane.” This statement is true. Viruses possess only nucleic acid and protein. They do not possess the basic machinery of the cell or a cell wall or a cell membrane. Viruses contain only a specific kind of nucleic acid along with a protein capsid. Cell membranes are usually present in animal cells, while cell walls are present in plant cells.
d) “Viruses grow in response to their environmental conditions.” This statement is false. Viruses do not grow in response to their environmental conditions. Since viruses do not possess the basic machinery of the cell, they cannot grow like other cells. Unless and until they infect a host cell, they cannot grow or reproduce. They do not have the ability to respond to stimuli from the outer environment like other organisms. Hence, the correct option is (c) viruses lack a cell membrane.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 2SA
The five phases of a generalized lytic replication cycle can be described in the following way:

Attachment:
The bacteriophage needs to come into contact with a bacterial cell for attachment to occur. Contact with a host bacterial cell occurs by random collision. The bacteriophage attaches to the cell membrane of the bacterial cell with the help of the tail fibers. The tail fibers attach to the receptor proteins on the cell membrane of the bacterium.
Entry:
Once the step of attachment is complete, the phage makes a small hole in the cell membrane of the host. This is done by using the enzyme lysozyme. This enzyme weakens the peptidoglycan of the cell membrane. The tail sheath of the phage contracts and forces a hollow tube through the cell wall membrane. The genome of the virus is then pushed inside the cell through this hole. The protein coat is left outside the cell.
Synthesis:
Once the genome of the virus enters the host bacterial cell, it degrades the bacterial genome. The viral genome orders the host machinery to start the synthesis of the daughter virions based on the code present in the viral genome. The process of transcription and translation occur as usual. The enzyme lysozyme is also synthesized which weakens the cell membrane of the bacterium from within. This is necessary for the lysis of the host cell later on in the cycle.
Assembly:
The different components of the virus are synthesized separately and then fitted together. This step is called assembling of the virus or assembly. Sometimes, a piece of the bacterial genome gets incorporated into the daughter virus by mistake. This later leads to a process called transduction.
Release:
By the time assembly ends, the work of lysozyme on the cell membrane is also completed. After the completion of the synthesis of all the daughter virions, the host cell bursts to release the newly synthesized daughter virions into the surroundings.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 3CT
The similarities between computer viruses and biological viruses are given below:

Self-spreading nature.
Reproductive by causing more number of copies.
Spread to other cells/computers.
Damage the host.
Prevention can be done by antivirus/vaccination.
Cannot reproduce on its own that needs a host.

Besides, computer viruses are said to be alive in the computer. Once created, it infects the files and folders on the system. It is created on a computer and can infect the same computer and other computers as well. It can be transferred to other computers through email or any removable discs.
In contrast, biological viruses are said to be dead outside the cell. Outside the host cell, they cannot do anything. Only after infecting a host cell, they can reproduce and synthesize new viruses. Inside a host cell, they are said to be alive.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 3M
The term “retrovirus” matches with the phrase “transcribes DNA (deoxyribonucleic acid) from RNA (ribonucleic acid).”
In most organisms undergoing metabolism, the genome is DNA. This genome contains all the required codes for the synthesis of all proteins, enzymes, and cell components. When a cell wants to synthesize any enzyme, it has to first transcribe the part of DNA, which is specific for that enzyme. In the process of transcription, DNA is converted to RNA. The RNA is then used as a template in the process of translation or protein synthesis.
The flow of genetic information is as shown below:
DNA → RNA → Protein
In retroviruses, since the genome is RNA, the procedure is bit different. These viruses usually have an enzyme called reverse transcriptase. This enzyme converts the RNA genome into DNA. Since this is a reverse of flow of information, the viruses are called retroviruses. The DNA formed is then incorporated into the genome of the host. Hence, the correct phrase is C. transcribes DNA from RNA.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 3MC
A virus that is specific for a bacterial host is called a phage.
a) A phage is a virus, which infects only bacterial cells. It infects and replicates within bacteria. Usually, phages which infect bacteria undergo either the lytic cycle or the lysogenic cycle. In the lytic cycle, the bacterial host cell ruptures to release the daughter virions. In the lysogenic cycle, the nucleic acid of the virus merges with the nucleic acid of the host. It then undergoes replication along with host DNA (deoxyribonucleic acid). Hence, this option is correct.
b) A prion is a small protein particle, which has the ability to infect. It lacks their own DNA, but can convert normal proteins into prions. The diseases caused by prions are usually transmitted by contaminated meat and affect the brain. These diseases are usually incurable. These prions do not infect bacterial cells. Hence, this option is incorrect.
c) A virion is a complete viral particle. It contains nucleic acid and a capsid. A virus present outside a cell is called a virion. These virions usually obtain their envelope from the membrane of the host. Hence, this option is incorrect.
d) A viroid contains circular fragments of RNA (ribonucleic acid), which have no protein capsid. These viroids cause disease in plants. Since viroids are not made up of cells and only made of RNA particles; they are treated as acellular organisms. In addition, they cannot grow, reproduce or have any metabolic reactions. Hence, this option is incorrect. Hence, the correct option is (a) phage.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 3SA
It is difficult to treat viral infections when compared to bacterial infections.
In the case of bacterial infections, antibiotics given are specific for prokaryotes. Hence, these drugs do not cause any harm to the eukaryotic cells in humans.
In the case of viral infections, viruses multiply inside host cells. Since viruses use the cell machinery, the host cells also need to be destroyed along with the virus. In addition, many viruses have antigenic markers on their capsids. These markers are specific for each virus. These markers are also responsible for the pathogenic nature of the virus.
In many viruses, the structure of these markers is changed repeatedly. A slight change in the sequence coding for these proteins can make a vaccine useless. When a vaccine or a drug is prepared to fight viral infections, a pathogenic protein is taken and drugs are synthesized against it.
This drug can work for some time. But, if the virus has changed the structure of its markers, the drug becomes useless. This is the reason why viral infections are hard to treat.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 4CT
Comparison of lysogeny by prophage and latency by provirus is given below:

In the lysogenic cycle, the genome of the virus integrates with the genome of the host cell. In the process of latency seen in animal viruses, the viral genome can either integrate with the host genome or can inactive in the cytosol of the host cell.
The viral genome, which inserts into bacterial genomes, is called a prophage, while viral genome inserts into the genome of animal viruses, is called a provirus.
In lysogenic viruses, the reactivation of the prophage can occur with change in environment or any other stimuli. This reactivation is known as induction in which the phage DNA (deoxyribonucleic acid) excises from the host genome. The excised prophage follows the lytic cycle, resulting in lysis of the cell. In latency, the reactivation of the provirus occurs when the immune system of the host becomes low. In the example of chicken pox virus, the reactivation causes different disease called herpes zoster.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 4M
The different parts of a bacteriophage are:
Head:
This consists of the protein capsid and the genome enclosed. The protein capsid consists of units called capsomeres. The genome can be either DNA (deoxyribonucleic acid) or RNA (ribonucleic acid).
Tail:
The tail part is the rest of the body of the phage.
Base plate:
This is needed for the attachment of tail fibers to the main body of the virus.
Tail fibers:
These tail fibers are used for attachment of the virus to the cell membrane of the host.
A bacteriophage has been given the name since it infects only bacteria. It is specific for bacteria and does not infect other organisms. Hence, the correct phrase is B. a virus that infects a bacterium.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 4MC
A naked virus has no membranous envelope.
a) A naked virus has no membranous envelope. A virus with an envelope is called an enveloped virus. The envelope on viruses is acquired only after lysis from the host cell. When lysis occurs, each virion gets a part of the host membrane as an envelope. So, the composition of the envelope would be the composition of the bacterial cell membrane. Hence, this option is correct.
b) A naked virus is not a virus, which has injected its DNA (deoxyribonucleic acid) or RNA (ribonucleic acid) into a host cell. When a virus wants to enter a bacterial cell, it attaches to the cell with tail fibers. After attachment, the genome of the virus is injected into the cell, while the empty capsid stays outside. This empty capsid is not called a naked virus. A naked virus is one without a membranous envelope. Hence, this option is incorrect.
c) A naked virus is not devoid of capsomeres. A capsomere is a unit of the capsid. The capsid is made up of many capsomeres. They are made up of protein and enclose the genome of the virus. This capsid remains outside the cell when a virus infects a host cell. A naked virus is one without a membranous envelope. Hence, this option is incorrect.
d) A naked virus is not one, which is unattached to a host cell. A virus, which is unattached to a host, is called only a virus. After a virus infects a host cell, it synthesizes daughter virions inside the host cell. These virions lack a membranous envelope and are called naked viruses. When they are released from the cell, they acquire the host membrane, which becomes the envelope for the virus. Hence, this option is incorrect. Hence, the correct option is (a) has no membranous envelope.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 4SA
The four different ways that viral nucleic acid can enter a host cell are as follows:

Entry of viruses into bacterial cells
Direct penetration
Membrane fusion
Endocytosis

The description for the above steps is given below:

Entry of viruses into bacterial cells:
The phage makes a small hole in the cell membrane of the host. This is done by using the enzyme lysozyme. This enzyme weakens the peptidoglycan of the bacterial cell membrane. The tail sheath of the phage contracts and forces a hollow tube through the cell wall membrane. The genome of the virus is then pushed inside the cell through this hole.
Direct penetration:
This process is used by naked viruses. In this method, the viral capsid attaches to receptors on the cell membrane. After attachment, the capsid sinks into the cell membrane. This creates a pore through which the genome enters the cell. The capsid is left outside.
Membrane fusion:
In some viruses, the entire capsid fuses with the cell membrane. This fusion occurs after attachment to cell receptors. The entire capsid is then released into the cell. The glycoproteins of the virus are left as a part of the cell membrane.
Endocytosis:
When the virus attaches to the receptors on the cell membrane of the host, it stimulates the cell to endocytize the entire virus. So, the whole virus enters the host cell. In such methods, the capsid is removed and the viral genome released.

Out of the four different methods given above, the first is regarding the infection of a bacterial host by a virus, while the other three are regarding the infection by animal viruses.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 5CT
In order to stop the viral infection in a crop, an agricultural microbiologist uses the following steps:

The onset of a viral infection begins with the attachment of the virus to the host cell. The virus attacks bacterial cell by attaching and then inserting the viral genome into the cell.
In the next stage the viral genome either undergoes a lytic cycle or lysogenic cycle. If it undergoes the lytic cycle, the viral genome initially degrades the host genome. Moreover, the host machinery synthesizes the daughter virions. The host cell then bursts to release the daughter virions.
In the lysogenic cycle, viral genome incorporates in the genome of the host. It then undergoes divisional cycles along with host genome. Additionally, viral genome is transferred to the host daughter cells. The viral genome is excised from the host genome by a process called induction. This happens due to many reasons like change in environment. After excision, the viral genome follows the lytic cycle as usual.

Thus, beginning step to either the lytic or the lysogenic cycle, attachment of the virus to the host cell. By preventing the attachment, we can prevent viral infections of the crop.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 5M
The term “capsid” matches with the phrase “protein coat of virus.”
The capsid is composed of many capsomeres. Capsomeres are a unit of the protein capsid which is present in a virus. This protein capsid encloses the genetic material of the virus. The genetic material of a virus can be either DNA or RNA.
The process of uncoating is the removal of the protein coat from the virus. This is usually seen when the virus infects a host cell. The coat is left attached to the cell membrane while the genome enters the host cell.
The capsid can be seen in the following figure of a bacteriophage:
microbiology-with-diseases-by-taxonomy-chapter-13-answers-5m
Hence, the correct phrase is D. protein coat of virus.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 5MC
Out of the given statements, the explanation to show whether they are true or not is given below.
a) “Viruses may have circular DNA.” This statement is true. The viral families, which have circular genomes, are Baculoviridae, Papovaviridae, and Polydnaviridae. Their genomes may be either DNA (deoxyribonucleic acid) or RNA (ribonucleic acid). Circular genomes may be double stranded or single stranded.
b) “dsRNA is found in bacteria more often than in viruses.” This statement is false. In RNA viruses, only the family of Reoviridae has double stranded RNA. The rest of the viral families have single stranded RNA as their genome. In DNA viruses, most of the families contain double stranded DNA. Only, the family Parvoviridae has single stranded DNA as its genome.
c) “Viral DNA may be linear.” This statement is true. The families of Adenoviridae and Herpesviridae have linear DNA as their genome. These genomes may be either DNA or RNA. Linear genomes may be double stranded or single stranded.
d) “Typically, viruses have DNA or RNA, but not both.” This statement is true. Virus families have either DNA or RNA as their genome, but not a combination of both.
Families containing DNA as their genome include Poxviridiae, Herpesviridae, Papillomaviridae, Polyomaviridae, Adenoviridae, Hepadnaviridae, and Parvoviridae.
Families containing RNA as their genome include Picornaviridae, Caliciviridae, Astroviridae, Hepeviridae, Togaviridae, Flaviviridae, Coronoviridae, Retroviridae, Orthomyxoviridae, Paramyxoviridae, Rhabdoviridae, Bunyaviridae, Filoviridae, Arenaviridae, and Reoviridae.
Hence, the only statement, which is false, is option (b) dsRNA is found in bacteria more often than in viruses.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 5SA
The processes of lysis and budding can be compared in the following table:
microbiology-with-diseases-by-taxonomy-chapter-13-answers-5sa
In both the above processes, the virus multiplies within the host cell and is released. All the steps of the lytic cycle except the last one are also followed in the process of budding. The two processes only differ in the method of release of virions from the host cell.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 6M
The term “envelope” matches with the phrase “a membrane on the outside of a virus.”
An envelope is the outer membrane of a virus. This membrane is acquired when the virus exits the host cell. A virus without a membrane is called a naked virus, while a virus with a membrane is called an enveloped virus.
The envelope of a virus can carry the antigenic markers of the virus. The space between the envelope and the capsid is filled with viral proteins called matrix proteins. The envelope of the virus has the exact components of the host cell membrane. It consists of a phospholipid bilayer with proteins scattered.
The difference between enveloped and non-enveloped viruses is shown below:
microbiology-with-diseases-by-taxonomy-chapter-13-answers-6m
Hence, the correct phrase is E. a membrane on the outside of a virus.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 6MC
When a eukaryotic cell is infected with an enveloped virus and sheds viruses slowly, this infection is called a persistent infection.
a) In a lytic infection, soon after infection of the host cell by the virus, the virus takes over the machinery of the host cell. It forces the host cell to synthesize daughter virions. After the synthesis of these virions, the host cell bursts releasing these daughter virions. Hence, this option is incorrect.
b) In a prophage cycle, soon after infection of the host by the virus, the genome of the virus merges with the genome of the host. When this happens, the viral genome is called a prophage. The genome of the virus replicates with the genome of the host and is also transferred to the daughter host cells. Only when there is some sort of environmental change or any sudden stimuli, the prophage excises itself from the genome and continues the lytic cycle. Hence, this option is incorrect.
c) A persistent infection occurs when daughter viruses are released from the host cell by the process of budding. This process is seen only in certain viruses. If all the daughter virions are released at the same time, it is not a persistent infection. But if the budding occurs over a period of time and viruses are being synthesized in the host cell continuously, this is called persistent infection. Hence, this option is correct.
d) A quiescent virus is one, which behaves almost like a lysogenic virus. It remains latent in the host cell after infection. These viruses show non-replicating nature and do not replicate or destroy the host cells. As these viruses are non-replicating, they cannot release daughter virions at all. Hence, this option is incorrect.
Hence, the correct option is (c) called a persistent infection.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 6SA
A virion contains nucleic acid and a capsid. A virus outside a host cell is known as virion. These virions usually obtain their envelope from the membrane of the host. A virion is a complete virus particle present outside the host cell.
A virus particle is one, which usually contains a capsid, genome, and an envelope. It is called a virus only, if it can infect and multiply inside host cells. Viruses can replicate only inside the living cells of the host. A virus can exist in an extracellular and intracellular state. Outside a host cell, a virus cannot replicate or grow on its own.
So, there is not much difference between a virus particle and a virion. Both are complete viral particles with all the components of a virus. A virus is called a virus inside a host cell, while it is called a virion outside a host cell.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 7M
The term “virion” matches with the phrase “complete viral particle.”
A virion is a complete viral particle. It contains nucleic acid and a capsid along with tail fibers. Virions can have an envelope or can be without an envelope. A virus outside a host cell is known as virion. These virions usually obtain their envelope from the membrane of the host.
A complete viral particle has all the components of the virus and is ready to infect other host cells. It has the required genome and the capsid made of protein. The capsid is made up of repeating units called capsomeres.
Incomplete viral particles are those particles, which lack any important component.
Hence, the correct phrase is F. complete viral particle.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 7MC
Another name for a complete virus is virion.
a) A virion is a complete viral particle. It contains nucleic acid and a capsid. Virions can have an envelope or can be without an envelope. A virus outside a host cell is known as virion. These virions usually obtain their envelope from the membrane of the host. Hence, this option is correct.
b) A viroid contains circular fragments of RNA (ribonucleic acid), which have no protein capsid. Since viroids are not made up of cells, but only made of RNA particles, they are not treated as complete viruses. Hence, this option is incorrect.
c) A prion is a small protein particle, which has the ability to infect. It lacks their own DNA (deoxyribonucleic acid), but can convert normal proteins into prions. The diseases caused by prions are usually transmitted by contaminated meat and affect the brain. Since they do not possess a genome, they are not complete viruses. Hence, this option is incorrect.
d) A capsid is the protein coat of the virus. The capsid is made up of many capsomeres. A capsomere is a unit of the capsid. They are made up of protein and enclose the genome of the virus. This capsid remains outside the cell when a virus infects a host cell. Since a capsid does not possess any genome of its own, it is not a complete virus. Hence, this option is incorrect.
Hence, the correct option is (a) virion.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 7SA
A provirus is similar to a prophage in many ways. Both prophages and proviruses have the same method of infecting a host cell. When a virus infects a host cell, its genome is injected into the cell. After this commons step, the genome can follow two ways.

Lytic cycle
Lysogenic cycle

In the lytic cycle, the host genome is degraded and the host machinery forced to synthesize new virions. In the end, the host cell bursts and dies.
In the lysogenic cycle, the viral genome integrates with the host genome. This viral genome is then called a prophage. It remains dormant in the genome until external factors activate it. When a virus infects a bacterial cell, it is known as a prophage. A virus is known as a provirus when it integrates with the genome of animal cells. The viral genome remains latent for a period of time.
The only difference between a prophage and a provirus is that a viral genome is called a prophage when it infects bacterial cells. It is called a provirus if it infects animal cells. The term of dormancy is called lysogeny in bacterial cells and latency in animal cells.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 8M
The term “provirus” matches with the phrase “dormant virus in a eukaryotic cell.”
A latent virus is known as a provirus. This virus remains dormant or latent in a eukaryotic cell. It can remain in the cytoplasm of the host cell or can become integrated with the chromosome of the cell. This provirus remains inactive for long periods of time, sometimes even for some years.
When a viral genome gets incorporated into a bacterial cell, it is known as a prophage. But, when a viral genome gets incorporated into a eukaryotic cell, it is known as a provirus. Both have the nature of remaining latent or dormant in the host cells.
In the case of bacterial cells, the process of being dormant is known as lysogeny, while in the case of eukaryotic cells, the process is known as latency. Hence, the correct phrase is A. dormant virus in a eukaryotic cell.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 8MC
Out of the following options, the explanation to show whether the viruses are latent or not is given below.
a) HIV:
The Human Immunodeficiency virus can be latent. When we see the infection by HIV, it is seen that the virus persists in some cells in a latent stage. When the virus lies latent in the host cells, retroviral drugs will not have any effect on HIV. Hence, this option is correct.
b) Chickenpox virus:
The chickenpox virus can be latent. When the chickenpox virus infects a person for the first time, it causes pustules which later on heal. The virus is not totally removed from the body. It lies latent in some nerve ganglion. When it is disturbed or reactivated by any stimulus, it causes the disease herpes zoster along the nerve it is present in. Hence, this option is correct.
c) Herpesviruses:
The herpesviruses can be latent. Chickenpox virus also comes under the category of Herpesviruses. The other latent virus in this category is the Herpes Simplex Virus. This virus also remains latent in neurons. Hence, this option is correct.
d) All of the above:
Since all the given three viruses show latency, we can say that option (d) is the correct option.
Hence, the correct option is (d) all of the above.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 8SA
The process of lysogeny can be described in the following way:

When a virus infects a cell, it injects its genome into the host cell.
After the viral genome enters the cell, it integrates with the host genome. This viral genome is then called a prophage.
It replicates along with the bacterial genome and is passed to the daughter bacterial cells.
It remains dormant in the genome until external factors activate it. This process is known as induction.
If it is activated, it then follows the lytic cycle where the host genome is degraded.
Then, the host machinery is forced to synthesize new virions by using the code of the viral genome.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 9M
The term “benign tumor” matches with the phrase “harmless neoplastic cells.”
A benign tumor is an abnormal growth of cells seen in any part of the body. These tumors usually do not cause any problem since they grow very slowly and do not cause the formation of tumors in other parts of the body. These tumors can only compress the surrounding tissue, but cannot metastasize.
Benign tumors are made up of harmless neoplastic cells, which can be easily removed by surgery. Once removed, usually benign tumors do not return and the patient can live a normal life.
The cause of formation of these tumors might be environmental factors or infection by oncogenic viruses.
Hence, the correct phrase is J. harmless neoplastic cells.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 9MC
Out of the following statements, the explanation to show whether they are specific criteria for the family classification of viruses is given below.
a) The type of nucleic acid present:
The type of nucleic acid, whether it is DNA (deoxyribonucleic acid) or RNA (ribonucleic acid), is a specific criterion in the classification of viruses. Viruses are broadly divided as DNA viruses and RNA viruses based on the genome they possess. Since viruses possess either DNA or RNA but not both, it is a specific criterion for classification. Hence, this option is correct.
b) Envelope structure:
The presence or absence of the envelope acts as a criterion for the classification of viruses. Viruses without envelopes are called naked viruses, while viruses with envelopes are called enveloped viruses. Hence, this option is correct.
c) Capsid type:
The shapes of capsids in viruses are also a criterion in the classification of viruses. The different capsid shapes are helical, polyhedral, and complex. All the different shapes seen fall into these three categories. Hence, this option is correct.
d) Lipid composition:
The lipid composition of the virus is not a criterion for the classification of viruses. Since capsids are mainly made up of protein and the percentage of lipids is less, it cannot be a criterion for the classification of viruses. Hence, this option is incorrect.
Hence, the option (d) lipid composition is not the criterion for the classification of viruses.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 9SA
The envelope of a virus has viral specific glycoproteins and proteins attached to its surface. In the case of non-enveloped viruses, the specific glycoproteins are present on the capsid of the virus.
These specific glycoproteins and proteins act as markers for the recognition of host cells. These glycoproteins recognize the surface receptors on the surface of host cells. By this recognition, some viruses can attack specific host cells.
All viruses are not host-specific, but most of them are. Some viruses like HIV have specific proteins on its surface, which are specific for the receptors on immune cells. That is why HIV attacks the immune system in a person.
Animal viruses are specific for animal cells, while bacteriophages infect bacterial cells.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 10M
The term “cancer” matches with the phrase “invasive neoplastic cells.”
A cancer is an abnormal growth of cells seen in any part of the body. These tumors usually cause problems, since they grow very quickly and cause the formation of tumors in other parts of the body. These tumors can compress the surrounding tissue and can also metastasize.
Cancers are made up of invasive neoplastic cells, which cannot be easily removed by surgery. Once removed, usually cancers return and the patient has to be careful all his life for any signs of cancer in any part of his body.
The cause of formation of these tumors might be environmental factors or infection by oncogenic viruses.
Hence, the correct phrase is I. invasive neoplastic cells.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 10MC
A clear zone of phage infection in a bacterial lawn is a plaque.
a) A prophage:
A prophage is a virus whose genome has integrated with the genome of the host cell. This occurs in the lysogenic cycle. The viral genome replicates along with the bacterial genome and is transmitted to the daughter bacterial cells. This prophage can suddenly reactivate and excise itself from the host genome. It then follows the lytic cycle. Hence, this option is incorrect.
b) A plaque:
When a virus is allowed to infect a lawn of bacterial cells, it causes the formation of clear zones in the lawn. These zones are known as plaques. They represent dead bacterial cells. These plaques indicate that the virus has attacked the bacterial cells in the Petri plate. Hence, this option is correct.
c) Naked:
A virus is called naked when it does not have an envelope. The envelope of a virus is usually acquired from the cell membrane of the host after the lytic cycle. Naked viruses are usually those which are newly synthesized inside the host cell. Those viruses with an envelope are called enveloped viruses. Hence, this option is incorrect.
d) A capsomere:
A capsomere is a unit of the capsid. The capsid is the protein coat which encloses the genome of the virus. It does not play any role in infecting hosts since it is left outside the host cell. A capsomere is present in almost all viruses. Hence, this option is incorrect.
Hence, the correct option is (b) a plaque which is the clear zone of phage infection seen in a bacterial lawn.

Microbiology with Diseases by Taxonomy Chapter 13 Answers 10SA
The comparison of diploid cell culture and continuous cell culture can be described in the following way:
microbiology-with-diseases-by-taxonomy-chapter-13-answers-10sa
Each method has its own advantages and disadvantages. Hence, it depends on the need of the researcher to use whichever method he thinks best.

Microbiology with Diseases by Taxonomy Chapter 12 Answers

May 26, 2018 by Raju

Microbiology with Diseases by Taxonomy Chapter 12 Answers

Microbiology with Diseases by Taxonomy Answers

Microbiology with Diseases by Taxonomy Chapter 12 Answers 1CM
microbiology-with-diseases-by-taxonomy-chapter-12-answers-1cm

Microbiology with Diseases by Taxonomy Chapter 12 Answers 1CT
There are some similarities in between the protozoan cysts and bacterial endospores. Both the structures are non-reproductive structures and share similarities in their metabolism. Both the protozoan cysts and bacterial endospores are resistant to drying and some disinfectants.
However, there are even differences between the protozoan cysts and bacterial endospores. The protozoan cysts are eukaryotic in nature, while the bacterial cysts are prokaryotic. Protozoan cysts are not as resistant as bacterial cysts for heat treatment and irradiation.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 1FB
The study of protozoa is called protozoology.
Protozoology is the study of protozoans. These are single-celled animals, which are eukaryotic, unicellular, motile, heterotrophic cells that lack cell wall. The scientists who study these microbes are protozoologists.
Hence, the correct answer is protozoology.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 1L
The photos given are labeled with the type of fungal spore and the type of spore, representing asexual or sexual is given below:

Ascospores are sexual spores.
Basidiospores sexual spores.
Conidia asexual spores.
Chlamydospores asexual spores.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 1M1
Mitosis begins after the cell has duplicated its DNA (deoxyribonucleic acid), so that there are two exact DNA copies. The cell partitions its replicated DNA equally between two nuclei. So, mitosis maintains the ploidy of the parent nucleus. If haploid nucleus undergoes mitosis forms two haploid nuclei; and a diploid nucleus undergoes mitosis produces two diploid nuclei.
Hence, the correct option is (e) diploid nuclei producing diploid nuclei.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 1M2
Fungi have cell wall, which is composed of a strong, flexible, nitrogenous polysaccharide called chitin. This is chemically identical to exoskeletons of insects and other arthropods like lobsters, crabs, and grasshoppers. It is a long polymeric chain of N-acetyl-glucosamine units, which are derivatives of glucose. Hence, the correct option is (a) fungal cell wall component.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 1M3
Chlorophyta are green algae, which have chlorophylls a and b, and use sugar and starch as food reserves. These share similar characters with plants. They are commonly seen in freshwater, terrestrial, and marine environments. There are some species which got specialized to survive under extreme conditions like deserts, hypersaline habitats, deep sea hydrothermal vents etc. Hence, the correct option is (C) green algae.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 1MC

A nucleus with a single set of chromosome is called as haploid nuclei. Generally eukaryotic nucleus has one or two complete set of the chromosomal portion of the genome. If it has two sets of chromosomes then it is called as diploid nuclei. For example gametes are haploid but zygote is diploid. Hence option (b) incorrect.
The zygotes formed due to union of sperm and egg. Here, the sperm and egg are haploid in nature they union form a diploid zygote. Hence option (c) incorrect.
They usually find in the intracellular fluids but not in the cytosol of eukaryotic-organisms. Hence option (d) incorrect. Hence the correct option is (A) contain one set of chromosomes.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 1SA
Comparison and contraction between the closely related terms:
Explanation
Chromatid:
Chromatid is a single daughter strand of a duplicated chromosome, which is joined by a centromere.
Chromosome:
Chromosome is physically distinct unit of the genome, which carries many genes. Chromosomal DNA (deoxyribonucleic acid) encodes all the genetic information.
Mitosis:
Mitosis is a form of nuclear division where the cell has previously replicated each of its chromosomes to separate into two identical sets of chromosomes. Moreover, two nuclei with the same ploidy are produced.
Meiosis II:
Meiosis II is the second phase of meiotic process. The products of meiosis II are the formation of four daughter cells each with one half of the number of chromosomes with the original parent.
Hypha:
Hyphae are the long, branched, tubular filaments of thallus of molds. They can be septate (divides into cells by cross walls called septa) and aseptate (no septa).
Mycelium:
Mycelium is the thallus of mold, composed of hyphae intertwined to form a tangled mass called mycelium.
Algal thallus:
Algae are the unicellular or colonial, which have simple multicellular bodies called thalli.
Fungal thallus:
It is a vegetative body of a fungus and is non-reproductive.
Water mold:
Water molds are not true fungi, but they resemble filamentous fungi and have finely branched filaments.
Slime mold:
Slime mold come under amoebozoa with lobe shaped pseudopodia by which they move and show genetic similarities like amoebozoa. They are of two types plasmodial molds and cellular slime molds.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 2CT
Saccharomyces (household yeast) is a metabolically versatile organism, which can catabolize biomolecules completely in the presence of oxygen. In the absence of oxygen, it can convert metabolic intermediates to useful substrates. Yeast can participate in the breakdown of sewage wastes and contribute to the establishment of diverse microbial community that can effectively recycle the materials in the septic tank. So, yeast is beneficial for home improvement.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 2FB
The study of fungi is called mycology.
Mycology is the branch of science that deals with the study of fungi. This study includes fungal genetics, biochemical properties, their taxonomy, their dangers to the humans, and their medicinal uses etc.
Hence, the correct answer is mycology.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 2M1
Meiosis is a nuclear division that involves the partitioning of chromatids into four nuclei. So, each nucleus receives only half the original amount of DNA (deoxyribonucleic acid). Diploid nuclei use meiosis to produce haploid daughter nuclei.
Hence, the correct option is (b) diploid nuclei producing haploid nuclei.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 2M2
Basidiocarps are fruiting bodies of basidiomycetes. These basidiocarps have tightly woven hyphae that extend into multiple, often club-shaped projections called basidia; at their ends they produce sexual basidiospores on each basidium. The basidiocarps are of two types; epigeous and hypogeous. The epigeous types are visible to naked eye and they are usually called mushrooms, while the hypogeous type basidia are underground and they are termed false truffles.
Hence, the correct option is (F) fungal spores formed on club-shaped hypha.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 2M3
Rhodophyta are red algae. These are characterized by the red accessory pigment phycoerythrin. It absorbs short wavelength blue light and photosynthesize at depths greater than 100 m. They are one of the ancient eukaryotic cells. In addition, they are one of the largest species on earth.
Hence, the correct option is (E) red algae.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 2MC
Mitosis is a type of nuclear division occurs in the somatic tissue of organisms, used in the healing process of damaged tissue. Mitosis have four different stages:
(a) The first step is prophase, in prophase condensation of chromatids takes place.
(b) The second step is metaphase, in metaphase the condensed chromatids are aligned at middle of the cell and attached with spindle fibers.
(c) The third stage is anaphase, in anaphase the condensed chromatids are pulled apart from each other towards opposite poles.
(d) The last stage is telophase, in telophase the cell restores its chromosomes, and nuclear envelope is formed around the new chromosomes. Single cell is divided in to two cells.
Here the option (a), (b), (c) are arranged improperly hence these options are incorrect.
Hence the correct option is (D) prophase, metaphase, anaphase, and telophase.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 2SA
Transport of nutrients through fungi:
Explanation
Fungi acquire nutrients by absorption. It is obtained by secreting catabolic enzymes outside their thalli and breaks large organic molecules into smaller molecules; thus, transport into thalli. In addition, some fungi are saprobes, which absorb nutrients from the remnants of dead organisms. The fungi, which derive the nutrients from living plants and animals, have modified hyphae called as haustoria.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 3CT
Penicillin is an antimicrobial agent, which acts against prokaryotic bacteria and interferes with the synthesis of peptidoglycan in cell walls. This is a characteristic and structural feature of most bacteria and is not present in eukaryotes. The organisms discussed in this chapter are eukaryotes and hence penicillin cannot act against them.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 3FB
The study of algae is called phycology.
Phycology is branch of science that deals with the algae, and often regarded as a subdiscipline of botany.
Algae are eukaryotic, photosynthetic organisms that live in wet environment. Even though they are photosynthetic like plant but differ from true plants by lack of roots, leaves, and stems.
Hence, the correct answer is phycology.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 3M1
Homologous chromosomes are chromosomes carrying similar or identical genetic sequences. They are the pairs of chromosomes having the same length, staining pattern, centromere position, and genes of a particular characteristic at corresponding loci. One of the homologous chromosomes is inherited from the organism’s mother and other from the father. An aligned pair of chromosomes is called tetrad.
Hence, the correct option is (d) carry similar genes.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 3M2
Zygospores are the sexual structurs of most zygomycetes. They are diploid reproductive spores of most protists and fungi. They are produced when two haploid cells get fuse together. They are also called zygosporangia. These are diploid fungal zygotes with a thick wall.
Hence, the correct option is (E) diploid fungal zygote with a thick wall.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 3M3
Chrysophyta are yellow-green algae because they contain orange-colored pigment called carotene. They are often called golden algae. Expect few species most of the species of this group are photosynthetic organisms. They are mostly present in lakes, and often become prey for zooplankton.
Hence, the correct option is (B) yellow-green algae.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 3MC
Prophase is the first phase in nuclear division. Here chromatids are formed by condensation of DNA molecules into visible threads.
Later one chromosome is formed from two identical chromatids at centromere and finally a set of microtubules is constructed in the cytosol region to form spindle. These are useful in separating sister chromatids to opposite poles.
The cell appears to have line of chromosomes across the mid region is takes place in metaphase hence option (a) is incorrect.
In the prophase the nuclear envelope becomes completely dissolved to release the chromatids hence the option (b) is incorrect.
The chromatids are separate in anaphase stage into individual chromosomes hence the option (d) is incorrect. Hence the correct option is (C) the cell constructs microtubules to form a spindle.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 3SA
Lichens are useful in environmental protection studies:
Explanation
Lichens are both fungi and photosynthetic microbes. Moreover, they do not grow well in polluted environments, so they are used as sensitive living assays for monitoring air pollution. If the lichen content is less then it is considered that the environment area is not polluted. Thus, ecologists considered lichens as living assays for monitoring air pollution.
Lichens reproduce both sexually and asexually. In asexual mode of reproduction, fragment of the thallus break and grows into lichen. Lichens with ascomycetes fungi reproduce sexually by producing disc shaped apothecia in which spores are formed.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 4CT
Filamentous fungi can be distinguished from colorless algae in the following aspects:
microbiology-with-diseases-by-taxonomy-chapter-12-answers-4ct

Microbiology with Diseases by Taxonomy Chapter 12 Answers 4FB
Fungal diseases are called Mycoses.
Mycoses are the fungal diseases of plants, animals and also humans. Dutch elm disease is a mycosis of elm trees. Athlete’s foot is a disease of humans. Localization of fungal spores on skin or inhalation of fungal spores may cause mycoses. Hence, the correct answer is mycoses.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 4M1
Crossing over is a process in which the homologous chromosomes exchange sections of DNA (deoxyribonucleic acid) in a random fashion in late prophase I step of meiosis. It results in recombination of DNA and has different genetic makeups from their siblings.
Hence, the correct option is (c) results in genetic variation.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 4M2
The vegetative, non-reproductive body of a fungus is called thallus. It is an undifferentiated vegetative tissue. It is seen in different groups of organisms such as fungi, liverworts, algae, lichens, etc. any structure that resembles thallus, is known as thalloid, or thalline, or thallose.
Hence, the correct option is (C) fungal body.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 4M3
Phaeophyta are brown algae, which contain xanthophylls (brown pigment), laminarin, and oils. Phaeophyta are in the kingdom stramenopila. They are mostly seen in marine and they are multicellular in nature. They constitute large group. They play an important role by acting as food for most marine organisms.
Hence, the correct option is (D) brown algae.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 4MC
Cytoplasmic division occurs with telophase of mitosis, but in some algae and fungi it may be postponed or may not occur at all. In this condition by repeated mitosis it produces multinucleate cells called coenocytes.
Mycosis is a disease condition caused by the fungal spores or fungal pathogenic parts. Hence option (a) is incorrect.
The haustoria are the modified hyphae used for the absorption of nutrients from dead and decay organisms. Hence the option (c) is incorrect. Hence the correct option is (C) coenocytes.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 4SA
Distinction between colorless alga and filamentous fungus:
Explanation
The group of euglenozoa is called as euglenids. They are photoautotrophic, unicellular microbes with chloroplasts containing light absorbing pigments. Moreover, the light absorbing pigments include chlorophyll a, b, and carotene. In addition, euglenids are similar to animals, which lack cell walls having flagella and are chemoheterotrophic phagocytes.
Hence, they share both plant and animal characteristics, so it is a challenge to classify euglenids for taxonomists.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 5CT
Protozoa are highly disparate and diverse group organisms, which has characteristics like eukaryotic, lack of cell wall, and being unicellular. These are also diverse in their metabolism, structures, locomotion etc. and can cause different diseases; while the algae are just beneficial organisms and are not harmful like protozoa. These are like plants and act as primary producers in oceans.
So, scientists as a group spend more money and time in studying protozoa than they do studying algae.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 5FB
Amoebae with stiff pseudopodia and silica shells are radiolarians.
The radiolarians are protozoans that belong to the super-group Rhizaria together with Foraminifera, and Cercozoa. They can produce intricate skeleton made up of minerals. Radiolarians have needle like pseudopodia, which contain bundles of microtubules within them. These pseudopodia render buoyancy to the Radiolarians. Hence, the correct answer is radiolarians.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 5M1
Cytokinesis is the process of cell division in which cytoplasm of the single eukaryotic cell is divided into two daughter cells. This process occurs during the late stages of mitosis. The process of cytokinesis is different in both animal and plant cells. A contractile ring is formed in animal cells, whereas plant cells construct a cell plate in the middle of the cell. Hence, the correct option is (a) cytoplasmic division.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 5M2
Ascomycota species like molds and yeasts are characterized by the formation of haploid ascopores with in a sac called asci. Ascospore is a spore present inside the ascus. In general, each ascus carries eight ascospores, which are produced by meiotic division followed by mitotic division.
Hence, the correct option is (D) fungal spores formed in a sac.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 5M3
Cercozoa are organisms belong to protists. This group includes most flagellates and amoeboids, which gains the food using pseudopods. Cercozoa are closely related to Foraminifera and Radiolaria. These have thread like pseudopodia and calcium carbonates shells. Hence, the correct option is (a) Foraminifera.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 5MC
Septate hyphae are branched, tubular filaments with cross walls found in large fungi.
Aseptate hyphae are not divided by septa or cross walls. Aseptate hyphae are multinucleate and have coenocytic condition. Hence the option (b) is incorrect.
The modified fungal hyphae are called Haustoria. They are used for the nutrient absorption from the dead and decay organisms, there is no existence of septate and aseptate haustoria. Hence the option (c) is incorrect.
The dimorphic mycelia are the existence of both mycelium and yeast like bodies. Hence the option (d) is incorrect. Hence the correct option is (A) Septate hyphae.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 5SA
Scientists studied extensively on protozoa on comparison with algae:
Explanation
Algae are simple, eukaryotic phototrophic organisms, which carryout photosynthesis. Moreover, they are several economic benefits of algae, which include:

They are used in health care and biofuel industries.
They reduce the inflammation of colon.
They are used to thicken ice creams, toothpastes, and syrups.
They are used for salad dressing and snack food.
Algae use sunlight for photosynthesis, so which naturally produces natural biomass oil product.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 6CT
Fungi are eukaryotic organisms; their metabolism is similar to that of humans, whereas bacteria have significant differences in structure and metabolism when compared with human. Most drugs affect the metabolic processes. So, it is much easier to find chemicals that are toxic to bacteria, but not to humans than it is to find chemicals toxic to fungi, but harmless to humans. Hence, there are more antibacterial drugs than antifungal drugs.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 6M2
Lichens are both fungi and photosynthetic microbes like cyanobacteria or less frequently like green algae. Lichen has hyphae of the fungus, which is usually an ascomycete. It surrounds the photosynthetic cells and provides nutrients, water, and protection. Algae or cyanobacteria provide the fungus with products of photosynthesis like carbohydrates and oxygen.
Hence, the correct option is (B) fungus + alga or bacterium.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 6MC
Chlamydospores are the asexual fungal spores with a thickened cell wall inside the hyphae. They formed during the unfavorable conditions.
Sporangiospores are produced inside a sac called sporangium form the fungal division zygomycota. Hence the option (a) is incorrect.
Conidiospores are produced at the tips or sides of hyphae (or) conidia. Hence the option (b) is incorrect.
Blastospore are asexual fungal spore is formed by the budding mechanism. Hence the option (c) is incorrect. Hence the correct option is (D) Chlamydospores.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 6SA
There are more antibacterial drugs on comparison with antifungal drugs:
Explanation
Parasitic worms are not microorganisms, but these are group of eukaryotes, relatively large animals called as parasitic helminths. Microbiologists have studied and observed the microscopic infective and diagnostic stages of the helminths, which are usually eggs or larvae in samples of blood, feces, and urine. Therefore, the study of microbiologists in large animals distinguishes the parasites microscopic forms from other microbes.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 7CT
Amoebae, diplomonads, and parabasalids lack mitochondria. Protozoan’s have metabolic pathways, which are similar to that of higher organisms. They require organic and inorganic materials for their metabolism. Even though they lack mitochondria, they can perform metabolic pathways like glycolysis. They have developed unique metabolic pathways that allow them to survive, multiply, and reproduce by scavenging nutrients from the host.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 7MC
The study of algae is called phycology. The scientists who studies about the algae are called as phycologists.
The classification of eukaryotic organisms is done by a zoologist. Hence option (a) is incorrect.
The persons who studied about the rusts, smuts, and yeast are called mycologist. Hence the option (c) is incorrect.
The parasitic worms are also called helminths. These are eukaryotic worm like organisms. Hence the option (d) is incorrect. Hence the correct option is (B) alterations of generations in algae.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 7SA
Ticks are arachnids, which have four pairs of legs. Fleas, lice, and mosquitoes are insects having three pairs of legs. They transmit diseases and are considered as disease vectors.

Tick-borne diseases are Lyme disease, Rocky Mountain spotted fever, tularemia, relapsing fever, and tick- borne encephalitis.
Fleas can serve as intermediate host for dog tapeworm. It transmits plague, which is carried by rat fleas.
Lice are the vectors involved in the epidemic outbreaks of typhus.
Mosquitoes carry pathogens that cause malaria, yellow fever, dengue fever, filariasis, viral encephalitis, and rift valley fever.

Hence, the microbiologists are interested in macroscopic ticks, fleas, lice and mosquitoes as they transmit diseases.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 8CT
Even without genetic sequences, mycologists can be certain. This is because even though the sexual stages are unknown, the analysis of rRNA (ribosomal ribonucleic acid) sequences has revealed that most deuteromycetes infact belong to Ascomycota; and none of the Septate, filamentous deuteromycetes will be shown to make zygospores.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 8MC
Sea weeds are generally thalli of large marine algae which are generally complex with branched holdfasts to anchor them to rocks, stem like stipes and leaf like blades. Sea weeds are organized in to various parts like stem, stipe, hold fast, and blade.

They are generally a mass of the unorganized body called thallus. The thallus is very in shape and size, between the sea weed species. Hence, the option (a) is in correct.
The anchoring body is called hold fast. That anchors the sea weed to, an unmovable object help to capture the nutrients. Hence the option (b) is incorrect
The blade is an organized mass of thallus. They act as flotation discs and sometimes changed into reproductive organs. Hence the option (d) is in correct. Hence the correct option is (C) stipe.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 8SA
Asexual fungi, which were earlier included in the deuteromycetes has never been expected to form zygospore, as it is a sexual structure formed during sexual reproduction in zygospore fungi.
Imperfect fungi (Deuteromycota): They are called imperfect fungi, as not sexual stage has yet been observed. The important characteristics include the following:

Reproduce asexually by means of shares.
Includes some edible fungi.
Some of the species before resemblance to ascomycetes and others to basidiomycetes & few to zygomycetes.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 9CT
Pneumocystis jiroveci that causes pneumonia was considered as a protozoan because it is a chemoheterotrophic in nature and lacks cell wall. But now, it is considered as fungi. They are reclassified as fungus because they have more structural and functional similarities to fungi and belong to taphrinomycotina branch of the fungal kingdom. The Pneumocystis jiroveci is now considered as yeast like fungus due to its similarities to the fungi.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 9MC
The algal blooms produce different type’s secondary metabolic products like agar-agar, phycoerythrin, and aliginic acid extra. Carrageenan is found in red algae or Rhodophyta in the cell wall.

The green algae belongs to the Plant kingdom have carotene, xanthophylls as their pigment molecules. The cellulose and glycoprotein found in cell wall. Hence the option (b) is incorrect.
The dinoflagellates are belong to the Alveolata kingdom have chlorophylls a, c₁, c₂; carotene as their pigment molecules. The cellulose is found in cell walls. Hence the option (c) is incorrect.
The yellow green algae is belong to the kingdom Stramenopila kingdom have chlorophylls a, c and xanthophylls as their pigment molecules. The cellulose, silica, calcium carbonate are found in cell wall. Hence the option (d) is incorrect. Hence the correct option is (A) red algae.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 9SA
Taxonomists classified Pneumocystis as fungus:
Explanation
Taxonomists classified organisms based on the structural similarities, nucleotide sequences, and cellular ultra-structure revealed by electron microscope. However, in modern classification there is no Protista class, instead based on their r RNA (ribosomal ribonucleic acid) sequenced into different kingdoms.
Therefore, nucleotide sequencing like, rRNA sequencing plays a major role in classifying the organisms.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 10CT
Dinoflagellates are eukaryotic, unicellular and lack cell wall; euglenids are eukaryotic, phototrophic, unicellular and colonial forms. So, these have both characteristics that are similar to protozoa and algae.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 10MC
The algal blooms store different type’s storage products like sugar, starch, glycogen, and oils extra. Golden algae or yellow-green algae contains chrysolaminarin which is a polysaccharide used as a storage product.

The euglenids belongs to the Euglenozoa kingdom have carotene, chlorophylls a as their pigment molecules. The cellulose and glycoprotein found in cell wall. The paramylon, oils, and sugar as their storage products. Hence the option (b) is incorrect.
The dinoflagellates are belong to the Alveolata kingdom have chlorophylls a, c₁, c₂; carotene as their pigment molecules. The cellulose is found in cell walls, starch and oils as their storage products. Hence the option (a) is incorrect.
The brown algae is belong to the kingdom Stramenopila kingdom have chlorophylls a, c and xanthophylls as their pigment molecules. The cellulose, aliginic acids are found in cell wall. The laminarin, oils as their storage products. Hence the option (d) is incorrect. Hence the correct option is (C) golden algae.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 10SA
Ascomycota forms ascospores with in sacs called asci. An ascus produces eight endospores by nuclear divisions.
Those nuclear divisions are elucidated as follows:

A dikaryon is formed by the fusion of multinucleate hyphal tips of opposite mating types.
This dikaryon reproduces to form hyphae, which are dikaryotic in nature.
In the dikaryon, the nuclei is diploid, and this nucleus undergoes meiosis and Cytokinesis to form four haploid cells within an ascus.
Each haploid cell undergoes mitosis and Cytokinesis to form two haploid ascospores, which result in eight ascospores inside the ascus.
These asci open to release their ascospores and germinate to produce hyphae.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 11MC
Diatoms are major group of algae, and belong to marine phytoplanktons; free floating photosynthetic microorganisms. Most of the diatoms are unicellular, and can exist as colonies. Diatoms are characterized by the presence of chlorophylls a and c and carotene. As they contain chlorophyll molecules, they are the producers in marine food chain. Hence, the correct option is (c) chlorophylls a and c and carotene.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 12MC
Water molds are not true fungi; they resemble filamentous fungi in having finely branched filaments. They differ from fungi in having tubular cristae in their mitochondria, cell walls of cellulose instead of chitin; have diploid bodies than haploid and spores having two flagella (one whip like and one hairy).
Hence, the correct option is (a) they have tubular cristae in their mitochondria.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 13MC
Trophozoite is a motile feeding stage of free-living aquatic and pathogenic protozoa. After entering the host, the Trophozoite undergoes schizogony and develops into a schizont, after releasing merozoites.
Hence, the correct option is (d) a trophozoite.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 14MC
Mitosis and meiosis are the two distinct cell division processes. Mitosis is the process of produces two identical daughter cells, whereas meiosis produces four haploid cells. In both mitosis and meiosis formation of spindle is common to separate the chromatids to the opposite poles of a cell.
Hence, the correct option is (a) spindle.

Microbiology with Diseases by Taxonomy Chapter 12 Answers 15MC
Stramenopila are major line of eukaryotes, among most of them are algae. They range from unicellular diatoms to multicellular kelp. Stramenopiles are characterized by hairy flagella at some stage of their life cycle. Major groups of stramenopiles include diatoms, brown algae, and oomycetes.
Hence, the correct option is (d) stramenopila.