Which of the following changes shifts the oxygen–haemoglobin dissociation curve to the RIGHT, favouring oxygen unloading at the tissues?
- A Decreased temperature
- B Decreased PCO2
- C Increased 2,3-bisphosphoglycerate (2,3-BPG) ✓
- D Increased pH (alkalosis)
Correct answer: C. Increased 2,3-bisphosphoglycerate (2,3-BPG)
Explanation
A rightward shift (decreased Hb–O2 affinity) is produced by increased 2,3-BPG, increased temperature, increased PCO2 and decreased pH (acidosis) — the conditions of metabolically active tissue (Bohr effect). Each of the other options shifts the curve to the left.
Reference: Guyton & Hall, Textbook of Medical Physiology, 14th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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