Which change shifts the oxygen-hemoglobin dissociation curve to the right, so that hemoglobin releases oxygen more easily to the tissues?
Answer and explanation
Correct answer: C. Increased PCO2 and decreased pH (the Bohr effect)
- Step 1: A right shift means lower oxygen affinity. Step 2. Acidosis, raised CO2, raised temperature and raised 2,3-BPG all lower affinity. Answer: increased PCO2 and decreased pH. Why not the others: cooling and low 2,3-BPG shift the curve left, and carbon monoxide shifts it left while lowering oxygen-carrying capacity.
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