Which of these correctly describes the chloride shift?

Question

Quizplus · Accepted Answer

The chloride shift refers to the movement of chloride ions (Cl⁻) into red blood cells (RBCs) in exchange for bicarbonate ions (HCO₃⁻) which occurs in the tissues. This is important because as RBCs release oxygen to the tissues, carbon dioxide (CO₂) is produced and converted to HCO₃⁻. Without the chloride shift, HCO₃⁻ would build up in RBCs and inhibit the conversion of CO₂, leading to acidification of tissues. The exchange of Cl⁻ for HCO₃⁻ helps maintain proper pH balance in the body. Option A is incorrect because in the lungs, the opposite exchange occurs - Cl⁻ leaves RBCs in exchange for HCO₃⁻. Option B is incorrect because carbonic acid is not exchanged for Cl⁻ during the chloride shift. Options D and E are also incorrect because CO₂ is not directly involved in the chloride shift.

Which of These Correctly Describes the Chloride Shift