Why does the sigmoidal shape of hemoglobin's oxygen binding curve facilitate efficient oxygen delivery to tissues with varying metabolic rates?

💡 Explanation

The sigmoidal curve, due to hemoglobin's cooperative binding, allows efficient loading in the lungs (high pO2) and unloading in tissues (varying pO2) because hemoglobin's affinity changes. Therefore, oxygen delivery adapts to metabolic needs, rather than remaining constant like a linear curve would.

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