Zoology - Breathing and Exchange of Gases Question with Solution | TestHub

CO₂ is carried by haemoglobin as carbamino-haemoglobin (about 20-25%). This binding is related to the partial pressure of CO₂. pO₂ is a major factor which could affect this binding. When pCO₂ is high and pO₂ is low as in the tissues, more binding of carbon dioxide occurs whereas, when the pCO₂ is low and pO₂ is high as in the alveoli, dissociation of CO₂ from carbamino-haemoglobin takes place, i.e., CO₂ which is bound to haemoglobin from the tissues is delivered at the alveoli.

RBCs contain a very high concentration of the enzyme, carbonic anhydrase and minute quantities of this enzyme is present in the plasma also and every 100 ml of deoxygenated blood delivers approximately 4 ml of CO₂ to the alveoli.