Read the following statements and choose the follwoing option: 1. Exchange of gases is not strictly restricted to alveoli 2. Solubility of gases affect the rate of diffusion 3. Partial pressure of oxygen is denoted by pCO2 4. About 97 per cent of O2 is transported by RBCs in the blood. 5. About 7 per cent of CO2 is carried in a dissolved state through plasma.

Step-by-step solution

Alveoli are the primary sites of exchange of gases. Exchange of gases also occur between blood and tissues. O2 and CO2 are exchanged in these sites by simple diffusion mainly based on pressure/concentration gradient. About 97 per cent of O2 is transported by RBCs in the blood. The remaining 3 per cent of O2 is carried in a dissolved state through the plasma. Nearly 20-25 per cent of CO2 is transported by RBCs whereas 70 per cent of it is carried as bicarbonate. About 7 per cent of CO2 is carried in a dissolved stat