Microbiology with Diseases by Taxonomy Chapter 11 Answers
Microbiology with Diseases by Taxonomy Chapter 11 Answers 1CT
Deeply branching bacteria:
The description, deeply branching bacteria is not correct. This is because the student defined that deeply branching bacteria are bacteria that are believed to have branched off from early normal bacterial life. Moreover, they have characteristics that are similar to other bacteria, such as being autotrophs and being able to withstand extreme environments.
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(b) Coccobacillus: these are both partially spherical and rod shaped.
(c) Bacillus: these are rod shaped bacteria.
(d) Vibrio: these are comma shaped.
(e) Spirillum: these are stiff and spiral.
(f) Spirochete: these are flexible and spiral.
(g) Pleomorphic: these have different shapes.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 1M
Bacillus anthracis :
Koch was a German physician, played an important role in establishing microorganisms to cause specific diseases. Moreover, he demonstrated certain bacteria known as Bacillus anthracis that is present in the blood of animals, but absent in healthy animals. He demonstrated that bacterium would cause anthrax by specific microorganisms Bacillus anthracis.
Bacillus anthracis is an agent of bioterrorism. It is facultative anaerobic rods and an endospore former. The endospores are either inhaled or enter the body through breaks in the skin. When they germinate vegetative cells produce toxins that kill surrounding tissues.
Hence, the bacterium, “Bacillus anthracis”, matches with the term, “anthrax.”
Thus, the correct option is (E) anthrax.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 1MC
- Snapping division is a type of binary fission with small variation. In snapping division only the inner portion of the cell wall forms a cross wall. This thickening of new transverse wall put tension on the outer layer of the old cell wall. And the tension swaps outer wall and it breaks with snapping movement leaving the daughter cells connected by a hinge of old cell wall material. So, this type of reproduction in prokaryotes results in a palisade arrangement of the cells.
Hence, the correct answer is option (c) snapping division.
- An endospore is a specialized structure produced by certain bacteria during harsh environmental conditions and enables bacteria to live for extended periods. During unfavorable conditions, a bacterium starts the formation of endospore. Hence, the option (b) is incorrect.
- Binary fission, a kind of asexual reproduction normally takes place in prokaryotes. During binary fission, the bacterial DNA replicates and the parent cells is divided into two identical daughter cells. Hence, the option (d) is incorrect.
- Pleomorphism is the existence of variant forms in some bacterial species in response to environmental conditions. However the pleomorphic division is not seen bacteria. Hence, the option (a) is incorrect.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 1MTF
All prokaryotes do not reproduce sexually, but reproduce asexually.
The most common type of reproduction carried by the prokaryotes is binary fission. It is often called prokaryotic fission. In this, the DNA (deoxyribonucleic acid) of the bacteria replicates and is pulled to the separate poles. During this process, the bacterium grows in size and starts splitting into two daughter cells. Thus, new cells arise from the pre-existing cells without any kind of sexual reproduction.
Hence, the statement “all prokaryotes reproduce sexually” is false.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 1SA
Bergey’s manual of systemic bacteriology is most authoritative reference in modern prokaryotic classification. Following are several criteria for grouping and classifying bacteria
- Morphological information about cells like staining and microscopic information, colonial characteristics which cannot identify more specific level than class.
- Physiological and biochemical information like metabolism of foods and byproducts produced.
- Serological testing- antibodies identify specific surface antigens.
- G-C content(guanine and cytosine)- good for clarifying taxonomic positions of groups (more closely related groups have more similar G-C content which is not sensitive enough for species identification.
- DNA probes.
- R-rna analysis which have 12 distinct branches.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 2CT
In presence of water and anaerobic conditions iron undergoes corrosion:
Iron oxide (rust) forms when iron is exposed to oxygen, particularly in the presence of water. Nevertheless, iron pipes typically corrode more quickly when they are buried in moist anaerobic soil than when they are buried in soil containing oxygen. This is because moist soil contains more amounts of oxygen for corrosion.
Additionally, microorganisms have the capability to form solid surface, which undergoes colonization and proliferate to form biofilms. The phenomenon of corrosion is more when metal iron is exposing to water, due to rapid proliferation.
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Veillonella belongs to genus of anaerobic cocci that live as a part of biofilm (plaque). The bacterium is gram negative and has the ability for lactose fermentation. Moreover, they exist as dental plaque and forms on the teeth of warm-blooded animals. The bacteria exist in the oral mucosa and intestine of mammals.
The process of fermentation done by the bacteria is as follows:
Lactate → acetate + 2 propionate + CO2 + H2O
Thus, the bacterium, “Veillonella”, matches with the term, “dental biofilm”.
Hence, the correct option is (B) dental biofilm (plaque).
Microbiology with Diseases by Taxonomy Chapter 11 Answers 2MC
Some filamentous cyanobacteria like Nostoc punctiforme, Anabaena, can withstand nitrogen starvation with the help of heterocysts. These are specialized nitrogen fixing cells. They fix atmospheric nitrogen using the enzyme nitrogenase. Hence, the option (d) is incorrect.
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A Vibrio is the bacterium that is slightly curved in shape, but not the bacterium Bacillus.
The Bacillus is a complete rod shaped bacterium. It is a gram-positive bacterium and it belongs to the phylum Firmicutes. The species of the Bacillus includes two types of species. They are free living species and pathogenic species.
Vibrio is gram-negative bacteria and is curved rod shaped or comma shaped. They are facultative anaerobes. They are mostly found in salt water. They are known to cause most of the foodborne diseases.
Hence, the statement “a Bacillus is the bacterium, which has slightly curved rod shape” is false.
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Extremophiles are the microbes which require extreme conditions of temperature, PH and salinity to survive. These include thermophiles and halophiles which are major prominent classes.
these are prokaryotes whose DNA, RNA, cytoplasmic membranes and proteins do not function properly at temperatures lower than 450C.
Example: Geogemma and Pyrodictium.
The geogemma genera live in hot acidic springs like terrestrial volcanic rifts. The pyrodictum live in deep-sea hydrothermal vents. Biological workers used the enzymes of thermophiles in recombinant DNA technology and also used in several industrial applications.
these inhabit extremely saline habitats like Dead Sea, Great Salt Lake and solar evaporation ponds. They live in 9 percent Nacl concentration to maintain their cell wall integrity.
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Axial filaments are absent in Gram-positive species:
Spirochetes are Gram negative bacteria, having axial filaments, which are motile spiral bacteria. Axial filaments are special types of flagella that wraps around the bacteria between its cell membrane and outer membrane. The type of filaments associated is only with spiral shaped bacteria called spirochetes, which are gram negative. Thus, Gram-positive species don’t have axial filaments.
The flagella are located outside of the cell, which allow the bacteria to move through various types of environments. In contrast, spirochetes allow the movement through viscous medium. This type of motility allows the bacteria to move, regardless of its location. By utilizing ATP (adenosine triphosphate), the flagella are able to beat and propel the cell.
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Clostridium perfringens is an anaerobic, spore forming rod shaped bacteria that exist in soil and sewage. Moreover, less number of cells is found in intestines of humans. Often food poisoning by perfringens results, due to consumption of foods contaminated with Clostridium perfringens more than 108 cells.
Additionally, C. perfringens grows rapidly in meat cooked in bulk where heat penetration is low. Under anaerobic conditions, the spores germinate in sealed cans and jars. Thus, Clostridium perfringens is a pathogenic bacterium that causes gangrene. Gangrene is a serious condition where it can cause myonecrosis, gas production, and sepsis.
Thus, the bacterium, “Clostridium perfringens”, matches with the term, “gangrene”.
Hence the correct option is (C) gangrene.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 3MC
Spirochaete is the term used to describe bacteria having long, spiral or highly coiled shape. This term is applied to any organism that belongs to the order Spirochaetales.
Hence, the option (d) is incorrect.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 3MTF
Yes, if you were to view Staphylococci, you should expect to see cluster of cells. Staphylococci refer to clusters. They appear round in shape and look like bunches of grapes under microscope. They are gram positive bacteria. Most of them are harmless and usually found on the surface of the skin.
Hence, the statement “if you were to view Staphylococci, you should expect to see cluster of cells” is true.
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These are blue green bacteria which vary in size, shape and method of reproduction. They range from 1µm to10µm in diameter. These are small motile filaments which glide away parental strands. Cyanobacteria have gliding capacity due presence of glycol calyx sheath around the body.
These are gram negative bacteria, aerobic, and soil dwelling bacteria which have unique life cycle for prokaryotes. These glides on slime trails, digests yeasts and other bacteria.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 4CT
Clostridium is an anaerobic bacterium isolated form exposed skin:
Clostridium is a strictly anaerobic bacterium, which dies in presence of oxygen. The obligatory anaerobes can also tolerate traces of oxygen due to the presence of superoxide dismutase enzyme, which acts as an antioxidant when exposed to oxygen. Hence, it can be isolated from the exposed surface of the skin.
Additionally, Clostridium is responsible for cause of death in living tissue. The bacteria invade through the wound, and multiply. The fermentation products are butyric acid, butanol, acetone, ethanol, and carbon dioxide.
Thus, the ability of microorganisms is avoided by, surgical removal of dead tissue, pressure above atmospheric pressure, and oxygen is toxic to bacteria.
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Clostridium botulinum :
Clostridium botulinum comes under beneficial microbes, which produce a deadly toxin, but it has been put to use for cosmetic purpose (botox) to remove the facial wrinkles. Additionally, small dose of the toxin is injected to facial muscles, which paralyzes or weakens the muscles and smoothen the skin, lasting for 6 months. High doses can paralyses, by spreading throughout the body and cause respiratory failure.
Thus, the bacterium, “Clostridium botulinum”, matches the term “botox”.
Hence, the correct option is (D) botox.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 4MC
An endospore is a specialized structure produced by certain bacteria during harsh environmental conditions and enables bacteria to live for extended periods. During unfavorable conditions, a bacterium starts the formation of endospore.
Endospores can remain alive for decades; remain alive in boiling water and also in a state of suspended animation. These have durability and potential pathogenicity and have defensive strategy against hostile or unfavorable conditions. Therefore, the options (a), (b), and (c) are correct. Hence, the correct answer is option (d) all of the above.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 4MTF
Elementary bodies are stable resting stages that do not metabolize, but will germinate when conditions improve. These bodies consist of RNA (ribonucleic acid) polymerase that is essential for the transcription of host genome. Even some organelles like ribosomes and ribosomal subunits are found in these bodies. All these characters help elementary bodies to remain stable under unfavorable conditions and to germinate when conditions improve.
Hence, the statement “initial bodies are stable resting stages that do not metabolize but will germinate when conditions improve” is false.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 4SA
The low G+C gram positive bacteria are classified within firmicutes phylum. These include three groups:
The main classes of low G+C bacteria are the clostridia species. These are rod shaped, obligate anaerobes which form endospores. The clostridia species produce different types of toxin molecules, these toxins act on human body causes serious illness. Example: C.botulinum.
The second classes of low G+C bacteria are mycoplasmas these are facultative or obligate anaerobes. Mycoplasmas are lack of cell wall, but they have thick plasma membrane with antigenic sterol molecules as protecting groups.
- Other bacilli and cocci:
These are composed of both bacilli and cocci which are significant in environmental, industrial and health care settings.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 5CT
According to Louis Pasteur “The role of the infinitely small in nature is infinitely large”. This is because bacteria are small organisms, which are useful in many ways in health, industry, and environments.
Some of the roles of microorganisms are listed below:
- Clostridium botulinum produce boutilinum toxin, which is used for wrinkles removal, as skin treatment.
- Lactobacillus is used to produce yogurt and pickles. Bacillus and cocci strains are very beneficial in human health and industry.
- Streptomyces produces important antibiotics, which are useful for human health.
- Nocardia used in degradation of pollutants and used for environmental purpose.
- Azospirillum and rhizobium are nitrogen fixers, which are important in agricultural industry.
- Acetobacter and Gluconobacter are used to synthesize acetic acid. Agrobacterium in genetic recombination studies.
- Zoogloea is useful in sewage treatment.
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Bacillus licheniformis :
Bacillus licheniformis is a gram positive, beneficial species of bacillus, which is found commonly in soil. Moreover it is also present on the feathers of birds like, sparrows and ducks. The bacterium facilitates the synthesis of the antibiotic, Bacitracin. In addition, it interferes with the synthesis of cell wall, RNA transcription, and damage to the cytoplasmic membrane of microorganisms.
Thus, the bacterium, “Bacillus licheniformis”, matches with the term, “bacitracin”.
Hence, the correct option is (L) Bacitracin.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 5MC
Extremophiles are the bacteria, which can live found in terrestrial volcanic habitats. Hence, the option (b) is incorrect.
Cyanobacteria can photosynthesize without having chloroplast, but they certainly contain chlorophyll. Photosynthesis is not possible without chlorophyll. Hence, the option (c) is incorrect.
Deinococcus radiodurans is an extremophilic bacterium, which can withstand more radiation. It also can survive dehydration, cold, vacuum, and acid conditions. Hence, the option (d) is incorrect.
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Archaea are classified into phyla based primarily on rRNA sequences, but not based on tRNA sequences. They were classified as a different group of prokaryotes in 1977 based on the sequences of rRNA genes. There are primarily two groups; archaebacteria and eubacteria. The rRNA sequences are widely used to bring out evolutionary relationships among different organisms, as they are found in all organisms from very primitive organism to very advanced organisms.
Hence, the statement “Archaea are classified into phyla based primarily on tRNA sequences” is false.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 5SA
Microbiology with Diseases by Taxonomy Chapter 11 Answers 6CT
Difference between bacterial endospore and actinomycetes spores:
Bacterial endospore is a dormant structure, which is very tough and non- reproducing in nature. Moreover, endospore can survive without nutrients and resistant to radiations, desiccation, and high temperatures. Moreover, endospore is formed during unfavorable conditions like shortage of nutrition. The tough coating of endospore is resistant to all unfavorable conditions. When favorable conditions arrive endospore reactivates.
Additionally, bacterial endospore is a vegetative cell that transforms into one endospore, which then germinates to form single vegetative cell. The difference between the bacterial endospores is not reproductive structures like actinomycete spores that are reproductive structures.
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Streptococcus is a gram positive cocci associated in chains. Staphylococcal burnt skin syndrome is also called bullous impetigo or Ritter’s disease. Moreover, it is a skin infection seen in small children. The toxins produced by Staphylococcus are mainly responsible for the cause of this syndrome.
Similarly, toxin B produced by Staphylococcus is scalded skin syndrome. Toxin B travels through blood to all parts of the body causing scalded skin syndrome. The sores caused by toxin are big and filled with liquid. When the sores break and liquid leaks out then disposing of skin in layers is observed. Skin is stripped off in the form of layers. They cause diseases like pharyngitis, scarlet fever, impetigo, pneumonia etc.
Thus, the bacterium, “Streptococcus”, matches with the term, “impetigo”.
Hence, the correct option is (K) impetigo.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 6MC
Spirilla are any of various bacteria that belong to the genus of gram-negative bacteria. They have elongated spiral form with tuft of flagella. Spirilla cannot fix nitrogen. Hence, the option (b) is incorrect.
Bacteroids is a genus of bacteria that belong to gram-negative bacilli. These bacteria are anaerobic, non-endospore forming. Bacteroids prefer mutualistic relationships. They cannot fix nitrogen. Hence, the option (c) is incorrect.
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Yes, Halophiles inhabit extremely saline habitats such as the Great Salt Lake. Halophiles generally depend on high concentration of salt to keep their cell walls intact and they are salt-loving organism. They stood as an example for extremophile as they love high salt containing environments.
Hence, the statement “Halophiles inhabits extremely saline habitats such as the Great Salt Lake” is true.
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The arrangement of bacterial cells mainly depends upon two aspects. They are shape of bacteria, and plane of division.
Cocci are the spherical shaped bacteria and bacilli are the rod shaped bacteria. Cocci divide along different planes but bacilli divide along a single plane.
The division of cocci appears in different planes because of its spherical shape. The divided cocci remains attached to each other forms a cluster of organisms namely tetrads, sarcinea, and staphylococci.
The bacilli are divided in single plane hence divided bacilli are attached side by side from long chains namely diplobacilli, streptobacilli, and palisade arrangement. So, the arrangements for cocci are more when compared with bacilli.
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Streptomyces are gram-positive bacteria, which belong to the genus of Actinobacteria. The name Streptomyces has been derived, due to the synthesis of antibiotic streptomycin. Moreover, the microorganisms exist predominantly in decaying vegetation and soil. The microorganisms produce useful synthesizing antibiotics like chloramphenicol and neomycin from natural origin. They produce several antimicrobial drugs like tetracycline, Chloramphenicol, and erythromycin. Tetracycline interferes with protein synthesis of microbes.
Thus, the bacterium, “Streptomyces”, matches with the term, “tetracycline”.
Hence, the correct option is (H) tetracycline.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 7MC
Bacteroids are obligatory anaerobic rods that inhabit the digestive tracts of humans. These digest cellulose that is indigestible by mammals. They can cause abdominal, pelvic, blood and other infections so they are the most common anaerobic human pathogens. Hence, the correct answer is option (a) Bacteroids.
Spirochaetes are a group of long, spiral shaped bacteria, some of which are mostly pathogenic to humans. They include the genera Spirochaeta, Borrelia, Treponema, and Leptospira. Hence, the option (b) is incorrect.
Chlamydia is a genus of bacteria that are obligate intracellular pathogens. They are gram-negative, aerobic bacteria. The infections caused by chlamydia pathogens are most commonly found sexually transmitted disease in humans. Hence, the option (c) is incorrect.
Methanopyrus is bacteria that belong to the genus methanogens. They are hyperthermophiles. Methanogens are non-pathogenic to humans. Hence, the option (d) is incorrect.
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Yes, the pigments located in thylakoids in phototrophic bacteria trap light energy for metabolic process. These bacteria trap light energy with photosynthetic lamellae. The membranes of thylakoids embed photosystems in it and help the cells to carry photosynthesis. Those photosystems and the pigments present in their membranes are used to trap energy from sunlight, in order to use it for various metabolic processes, including photosynthesis.
Hence, the statement “pigments located in thylakoids in phototrophic bacteria trap light energy for metabolic process” is true.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 7SA
Agrobacterium is an alphaproteobacterium which infects plants to form tumors called as galls. This bacterium inserts a plasmid called Ti which carries a gene for plant growth hormone into the chromosome of the plant. This growth hormone causes the cells of the plant to proliferate into a gall and in turn produce nutrients for the bacterium. So, scientists have discovered that they can insert any DNA sequence into the plasmid making it an ideal vector for genetic manipulation of plants.
The Ti plasmids present on bacterium have variety of genes they include:
- Origin of replication this sequence helps for replication of the plasmid to increase its copy number.
- The antibiotic resistance genes help for the selection of the gene inserted copies. The “vir gene” region produce virulence proteins can cause crown gall disease.
- Ti plasmid contains T-DNA region at this site we can insert foreign (or) required DNA sequences.
Hence, by this way Agrobacterium is used in Recombinant DNA technology.
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Corynebacterium diptheriae :
Diphtheria is caused by Corynebacterium diphtheria, which is an airborne pathogen. The pathogen is spread from infected to susceptible individuals through coughing, sneezing, and talking. The pathogen infects the tissues of the throat and tonsils. Diphtheria toxin released by the pathogenic strain inhibits protein synthesis, leading to cell death. Extensive tissue destruction causes damage to heart, kidneys, and liver. Death occurs due to suffocation. It is characterized by stones of phosphates within inclusions called metachromatic granules.
Thus, the term bacterium, Corynebacterium diphtheria, matches with the term, “diphtheria”.
Hence, the correct option is (Q) diphtheria.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 8MC
- Spirochetes belong to the phylum of double membrane bacteria. They are long flexible spiral shaped bacteria. Spirochetes contain axial filaments this characteristic distinguishes it from other bacterial species. Hence, the correct option is (b) spirochetes.
- Spirillum is the spiral shaped bacterium that belongs to the genus of Gram-negative bacteria. However, this bacterium is not flexible like spirochetes. Hence, the option (a) is incorrect.
- Vibrio is the bacteria that resemble curved rod shape, belongs to the genus Gram-negative. Hence, the option (c) is incorrect.
- Rickettsia are pleomorphic non-motile, Gram-negative bacteria. They are obligate intracellular parasites. Hence, the option (d) is incorrect.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 8MTF
Yes, most cyanobacteria form heterocysts in which nitrogen fixation occurs. These bacteria reduce nitrogen and ammonia by a process called nitrogen fixation. Many of these bacteria fix nitrogen in thick-walled cells called heterocysts.
The heterocysts are specialized for fixing nitrogen during the conditions like starvation. Other than cyanobacteria, they are observed in different bacteria like Nostoc punctiforme, Anabaena sphaerica, and Cylindrospermum stagnale.
Hence, the statement “most cyanobacteria form heterocysts in which nitrogen fixation occurs” is true.
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Proteobacteria phylum is a very large group of gram-negative bacteria which is divided into five classes:
These include variety of aerobes, capable of growing at low nutrient concentration. Most purple nonsulfur phototrophs are alphaproteobacteria. Some, members of the alphaproteobacteria are nitrifying bacteria.
These include nitrifying Nitrosomonas and pathogenic species like Neisseria(gonorrhea), Bordetella(whooping cough)
These constitute the largest class of Proteobacteria. These include purple sulfur bacteria, intracellular pathogens, facultative anaerobes that utilize glycolysis and the pentose phosphate pathway and pseudomonas.
These include Desulfovibrio which are important in the sulfur cycle and in corrosion of pipes. Bdellovibrio which is pathogenic to bacteria and Myxobacteria.
These include some important human pathogens like campylobacter and Helicobacter.
These are distinguished by small differences in their r RNA sequences.
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Gluconobacter is oval shaped bacteria and is gram negative. It belongs to alphaproteobacteria, which has the ability undergo fermentation in oxidizing alcohols and carbohydrates. Moreover, they can be used in vitamin C synthesis. The size of the genome is very small that is important in industry and environment. It is beneficial and useful in the synthesizes acetic acid (vinegar)
Thus, the term, “Gluconobacter”, matches with the term, “vinegar”.
Hence, the correct option is (I) vinegar.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 9MC
- Nitrogen fixers are called as alphaproteobacteria, which grow in association with the roots of plants where they convert atmospheric nitrogen to ammonia and make it available for plants as fixed nitrogen. Nitrifying bacteria derive electrons from the oxidation of nitrogenous compounds.Nitrification is the conversion of ammonia and ammonium to nitrate. Hence the correct answer is option (c) nitrogen fixers.
- Bacteria of the genus Nitrosomonas and Nitrobacter convert ammonia or ammonium to nitrate or nitrite to nitrate. Since they cannot convert nitrogen gas into ammonia, option (a) is incorrect.
- Nitrogenous is the term used to indicate compounds that contain nitrogen. Bacteria that convert nitrogen gas into ammonia are nitrogen fixers, but not nitrogenous bacteria. Hence, the option (b) is incorrect.
- Nitrification is the biological process by which ammonia is oxidized into ammonium, then into nitrite followed by the oxidation of nitrites to nitrates. Members of the genera Nitrosomonas and Nitrobacter performs this process as a part of nitrogen cycle. Hence, the option (d) is incorrect.
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No, a giant bacterium that is large enough to be seen without a microscope is Epulopiscium, but not Veillonella. Epulopiscium belongs to clostridia, which can be visible without a microscope. Veillonella is a genus of anaerobic cocci that live as part of biofilm (plaque) that forms on the teeth of warm-blooded animals.
Hence, the statement “a giant bacterium that is large enough to be seen without a microscope is veillonella” is false.
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Cyanobacteria are gram negative phototrophs. They range in size from 1µm to 10µm in diameter. They are true prokaryotic organisms, but they use chlorophyll-a in photosynthesis process like higher plants and algae. Some cyanobacteria species are motile move along the surfaces by gliding process. They commonly reproduce by binary fission, some species from thick walled akinete spores.
The name of blue green algae is changed into cyanobacteria due to color of the bacteria, because of their photosynthetic nature.
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Borditella is a pathogenic betaproteobacteria, which causes pertussis or whooping cough.
When the proteins obtained from the bacterium Bordetella pertussis is administered as a part of DTaP vaccine to children after birth. Moreover, it is also administered to adolescents, adults, and healthcare workers in the form of vaccines. Moreover, drugs such as ampicillin, tetracycline, and erythromycin kill the pathogen and prevent drug resistance strains.
Thus, the bacterium, “Borditella”, matches with the term, “pertussis”.
Hence, the correct option is (N) pertussis.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 10MC
Mycobacterium contains mycolic acid in their cell walls. They grow very slowly because they take much time and energy required to enrich their cell walls with high concentrations of long carbon-chain waxes and make the cells resistant to desiccation.Hence the correct option is (D) Mycobacterium.
Corynebacterium belongs to the genus of gram-positive, bacilli. Their distinctive cell wall predominantly contains meso-diaminopimelic acid any many repetitions of arabinogalactan and corynemycolic acid. There is no presence of mycolic acid in the cell walls of Corynebacterium.Hence, the option (a) is incorrect.
Listeria species are gram-positive, rod-shaped bacteria. The cell walls of these species contain ipoteichoic acids, in which glycolipid moiety is covalently linked to the terminal phosphomonoester of the teichoic acid. Mycolic acid is absent in Listeria. Hence, the option (b) is incorrect.
Nocardia belongs to the genus of gram-positive bacilli, which are catalase-positive. They are soil and water dwelling aerobes, sometimes resemble fungi. Only some of the species of Nocardia are partially acid fast due to the presence of intermediate length mycolic acid in their cell walls. Hence, the option (c) is incorrect.
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Yes, when environmental nutrients are depleted, myxobacteria aggregate in mounds to form fruiting bodies.
The myxobacteria are commonly called slime bacteria. They live in soil and feed insoluble organic matter. These divide by binary fission when nutrients are plentiful. But, whenever the nutrients are depleted, these bacteria aggregate as mounds and form fruiting bodies. Hence, the statement “when environmental nutrients are depleted, myxobacteria aggregates in mounds to form fruiting bodies” is true.
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Difference of nitrification and nitrogen fixation:
It is the process by which bacteria convert reduced nitrogen compounds such as ammonia into nitrate, which is more available to plants. For instance, the process facilitates the removal of nitrogen, by microbes to perform oxidation.
This process is involved in the conversion of atmospheric nitrogen into ammonia. For instance, the relationship leguminous plants and the nitrogen fixing bacteria is important. Since, the gaseous nitrogen present is converted into nitrates, which are usable by plants. Nitrogen is an active major participant of protein synthesis.
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Zoogloea is a betaproteobacteria mainly used for sewage treatment.
Zoogloea is aerobic, gram negative bacteria. They are chemoorganotrophic rod shaped bacteria. The bacteria are known for cell aggregates that are embedded in gelatinous matrices. In addition, they contain nitrogenous compounds and polysaccharides belonging to Betaproteobacteria. The bacteria exist in polluted water, mainly involved in sewage water treatment to form floc.
Thus, the bacterium, “Zoogloea”, matches with the term, “floc formation”.
Hence, the correct option is (P) floc formation.
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Azotobacter is mainly used for nitrogen fixation.
The genus Azotobacter is ovoid bacteria, which are egg-shaped. They are pseudomonads, soil-dwelling non-pathogenic nitrogen fixers. Moreover, they can be motile by using peritichous flagella, which surrounds them entirely. Their cells are variable and can be rod like or coccoid shaped. They are aerobic and can perform nitrogen fixation.
Thus, the bacterium, “Azotobacter”, matches with the term, “nitrogen fixation”.
Hence, the correct option is (O) nitrogen fixation.
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Desulfovibrio is an obligate anaerobe belongs to anaerobic group of Deltaproteobacteria. They use organic compounds or H2 as electron donor to carry out anaerobic respiration process. Moreover, they are sulfate reducing bacteria, which reduces sulfate (SO42-) to hydrogen sulfide (H2S).
Desulfovibrio, comes under the physiological group that does not have the ability to oxidize acetate and other fatty acid completely. The organisms use pyruvate, lactate, ethanol, and few fatty acids as electron donors. Thus, Desulfovibrio usually found in anoxic environment where there is presence of substrate to reduce. The process of microbial decomposition can make the habitat anoxic.
Thus, the bacterium, “Desulfovibrio”, matches with the term, “iron pipe corrosion”.
Hence, the correct option is (M) Desulfovibrio.
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Chlamydia is the genus for chlamydias, which are gram-negative cocci that grow and reproduce within the cells of mammals, birds, and few vertebrates. Chlamydia is caused by bacteria like Chlamydia trachomatis. They generally cause a sexually transmitted disease called lymphogranuloma venereum, which is the most common disease in the United States. Moreover, Chlamydia remains untreated in women. The infections show few outward signs because the diseases are asymptomatic. The infections of the lower reproductive tract are usually mild or asymptomatic, especially in women.
Thus, the bacterium, “chlamydia”, matches with the term, “lymphogranuloma venereum”.
Hence, the correct option is (F) lymphogranuloma venereum.
Microbiology with Diseases by Taxonomy Chapter 11 Answers 15M
The class Cytophaga is slender, rod, and often has pointed ends. The class Cytophaga can actively degrade polysaccharides and play an important role in mineralization of organic matter.
Cytophaga are bacteriods of aquatic gliding rod-shaped aerobes with pointed ends. These bacteria can degrade complex polysaccharides like cellulose, agar, pectin, and chitin to cause damage to wooden boats and degrades raw sewage. Hence, the correct option is (A) wood damage.