Normal PCO2 of arterial blood is:

Ans: b (40 mmHg.) Ref:Ganong, 22nd ed, p. 607Partial pressure (mmHg) Arterial bloodVenous bloodPO29540PCO24046Carrying capacityoxygen19.6ml/dl15.6ml/dl Carbon dioxide49ml/dl53ml/dl1 gm Hb can carry 1.39 ml of oxygen, when fully saturated.1.34 ml oxygen in vivo.1 gm Hb carries 3.34 mg Iron in it.Oxygen entering the body per minute= 250 ml.Oxygen leaving the body per minute= 200 ml (288L/day).PH of arterial blood - 7.4 and pH of venous blood - 7.36Haematocrit of venous blood increase by 3%Chloride shift takes about 1 second to occur.