What is the chloride shift in red blood cells?

1. A Option A: Loss of Cl⁻ ions from plasma into the alveoli
2. B Option B: Movement of Cl⁻ ions out of red cells as O₂ enters
3. C Option C: Replacement of Fe²⁺ by Cl⁻ in haemoglobin
4. D Option D: Movement of Cl⁻ ions into red cells as HCO₃⁻ ions diffuse out

Answer checked 11 October 2026 · How we write and check questions