If one hold his breath after expiration for about 30 sec., would there still be occurring any exchange of respiratory gases in the lung during this period? Explain.
Yes, if someone holds his breath after expiration for about 30 sec there would still be occurring exchange of respiratory gases in the lungs during this period because after a normal expiration some amount of air remains in our lungs which we call as residual volume which is 1100-1200 ml. When we uphold our breath the exchange of this residual volume gases will continue in our lungs.