Mechanism Of Respiratory System
Respiratory centre is in Medulla Oblongeta.
Mechanism of breathing involves Two Phases.
(A) Inspiration
(B) Expiration
Inspiration:
Intercostal and phrenic muscles of diaphragm contract to increase thoracic cavity, therefore outside rushes inside.
Expiration:
Intercostal & phrenic relex muscles.
Due to decrease of thoracic cavity air pressure within lungs increase, the greater pressure within lungs force ful air from lungs to outside of body.
Gaseous Exchange:
Gaseous exchange occur in Alveoli following pressure gradient O2 from high pressure in alveoli diffuse into blood & CO2 from blood in alveoli.
Gaseous Transport:
O2 is carried by haemoglobin (in RBC). 100 ml of blood can carry ~20 ml of O2 max, CO2 is transported in form of bicarbonates in plasma.