A patient with chronic anemia experiences increased fatigue during exercise, even with supplemental oxygen. Which mechanism explains why supplemental oxygen provides limited relief despite elevated arterial PO2?

💡 Explanation

Impaired hemoglobin cooperative binding reduces oxygen unloading in tissues, because hemoglobin's affinity for oxygen remains high even at lower PO2, therefore oxygen is not released effectively to the muscles during exercise, rather than the other options which would not cause the same issue.

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