Exemplar Problems

Question:

What is the Oxygen Dissociation Curve, and why is it sigmoidal in shape?

Answer:

The Oxygen Dissociation Curve is a graphical representation of the relationship between the partial pressure of oxygen (PaO2) in the blood and the saturation of hemoglobin with oxygen (SaO2). It is sigmoidal in shape because hemoglobin’s affinity for oxygen changes with varying oxygen concentrations. At low oxygen levels, such as in tissues, hemoglobin has lower saturation, facilitating oxygen release. At high oxygen levels, like in the lungs, hemoglobin becomes highly saturated, allowing efficient oxygen loading.