question_answer 5)

What will be the pO2 and pCO2 in the atmospheric air compared to those in the alveolar air? (i) pO2 lesser and pCO2 higher (ii) pO2 higher and pCO2 lesser (iii) pO2 higher and pCO2 higher (iv) pO2 lesser and pCO2 lesser  

Answer:

(i) In the alveolar tissues, where low pO2, high pCO2, high H+ concentration, these conditions are favourable for dissociation of oxygen from the oxyhaemoglobin. (ii) When there is high pO2, low pCO2, less H+ concentration and lesser temperature, the factors are all favourable for formation of oxyhaemoglobin. (iii) When pO2 is high in the alveoli and pCO2 is high in the tissues then the oxygen diffuses into the blood and combines with oxygen forming oxyhaemoglobin and CO2 diffuses out. (iv) When pO2 is low in the alveoli and pCO2 is low in the tissues then these conditions are favourable for dissociation of oxygen from the oxyhaemoglobin.