A patient's arterial blood pH decreases during intense exercise. Which effect dominates hemoglobin's oxygen-binding affinity at the working muscle tissue?

💡 Explanation

The Bohr effect describes hemoglobin's decreased oxygen affinity at lower pH (higher H+ concentration) because the increased proton concentration stabilizes the deoxy form of hemoglobin, facilitating oxygen release. Therefore, the Bohr effect enhances oxygen unloading at metabolically active tissues rather than other factors dominating, which have smaller effects under these conditions.

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