Compared to normal levels, a shift in the HbO₂ curve to the right has which of the following effects?
1) The affinity of Hb for O₂ decreases.
2) The Hb saturation for a given PO₂ falls.
3) The Hb saturation for a given PO₂ rises.

Question

Quizplus · Accepted Answer

When the HbO₂ curve shifts to the right, it means that the affinity of Hb for O₂ decreases. This is because it takes a higher PO₂ concentration to achieve the same level of Hb saturation as in the normal curve. Therefore, option 1 is correct. As for option 2, it is also correct because the Hb saturation for a given PO₂ falls due to the decreased affinity. However, option 3 is incorrect because the Hb saturation for a given PO₂ cannot rise when the curve shifts to the right.

Compared to Normal Levels, a Shift in the HbO2 Curve

Compared to Normal Levels, a Shift in the HbO₂ Curve