Assertion : Chloride shift is exchange of `Cl^(-)` of plasma and `HCO_(3)^(-)` of RBCs.
Reason : Chloride shift maintains an acid base balance between RBCs and plasma.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true and reason is not the correct explanation of assertion
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Answer

B

Explanation

Chloride shift is the movement of chloride ions `(Cl)` into red blood cells. Carbon dioxide reacts with water to form carbonic acid in the red blood cells. The carbonic acid then dissociated into hydrogen carbonate ions `(HCO_(3)^(-))` and hydrogen ions `(H^(+))`. The plasma membrane is relatively permeable to negative ions. Therefore, the hydrogencarbonate ions diffuse out of the cell into the plasma, leaving the hydrogen ions, which create a net positive charge, this is neutralised by the diffusion of chloride ions from the plasma into the cell.