Question

At PO2 = 40 mm Hg, which statement about the saturation of either myoglobin (Mb) or hemoglobin (Hb) is true? At PO2 = 40 mm Hg, which statement about the saturation of either myoglobin (Mb) or hemoglobin (Hb) is true? At this partial pressure of oxygen, neither Hb nor Mb would be fully saturated with oxygen. At this partial pressure of oxygen, both Hb and Mb would be equally saturated with oxygen. At this partial pressure of oxygen, Mb would be almost completely saturated but Hb would not. At this partial pressure of oxygen, Hb would be completely saturated but Mb would not.

Answer 1

At this partial pressure of oxygen, Mb would be almost completely saturated but Hb would not.

Step-by-step explanation:

The oxygen saturation curves for Mb and Hb are quite different. The curve for Mb is hyperbolic while that for Hb is sigmoidal.

Mb reaches oxygen saturation before Hb.

Thus, at a partial pressure of 40 mmHg, Mb is almost completely saturated but Hb is not.