During the Bohr effect, what change occurs to the oxyhemoglobin dissociation curve?

During the Bohr effect, what change occurs to the oxyhemoglobin dissociation curve?

• A. It causes a leftward shift of the dissociation curve
• B. It causes a rightward shift of the dissociation curve
• C. It does not affect the curve
• D. It reduces the rate of oxygen binding at the lungs

Answer: (B)

The Bohr effect describes how CO2 and pH changes influence hemoglobin’s oxygen affinity. When CO2 is high and pH is lowered in tissues, hemoglobin releases oxygen more readily, which shows up as a rightward shift of the oxyhemoglobin dissociation curve. In practical terms, at the same PO2, hemoglobin is less saturated, and the P50 value increases, meaning more oxygen is delivered to metabolizing tissues. In the lungs, CO2 is removed and pH rises, shifting the curve back to the left to favor oxygen uptake. So the rightward shift is the best description of the Bohr effect.

The Bohr effect describes how CO2 and pH changes influence hemoglobin’s oxygen affinity. When CO2 is high and pH is lowered in tissues, hemoglobin releases oxygen more readily, which shows up as a rightward shift of the oxyhemoglobin dissociation curve. In practical terms, at the same PO2, hemoglobin is less saturated, and the P50 value increases, meaning more oxygen is delivered to metabolizing tissues. In the lungs, CO2 is removed and pH rises, shifting the curve back to the left to favor oxygen uptake. So the rightward shift is the best description of the Bohr effect.