NEET Biology Breathing And Exchange Of Gases Based Practice Questions & Answers with Viewers Discussion and Detailed Explanation

Answer: (a)

$CO_{2}$ enters RBC and reacts with water to form carbonic acid. Carbonic acid dissociates to form bicarbonate and hydrogen ions. Some bicarbonate ions are transported in erythrocytes while some diffuse into the blood plasma. The exit of bicarbonate ions change the ionic balance between the plasma and erythrocytes. To restore this balance chloride ions diffuse from plasma into erythrocytes. Due to this the pH of blood is maintained.