Which factor is least likely to contribute to a right shift in the oxygen dissociation curve?

A right shift in the oxygen dissociation curve indicates that hemoglobin has a decreased affinity for oxygen, which facilitates the release of oxygen to the tissues. Several factors can contribute to this rightward shift:

Increased pCO2 is one of the factors that lead to enhanced oxygen unloading. Elevated levels of carbon dioxide result in the formation of carbonic acid, which lowers the pH (increased acidity) and causes hemoglobin to release oxygen more readily.

Increased temperature also promotes a right shift. Higher temperatures typically occur during periods of increased metabolic activity, which corresponds with a need for more oxygen delivery to tissues.

The presence of 2,3-DPG (2,3-diphosphoglycerate) in red blood cells is crucial as it binds to deoxygenated hemoglobin and stabilizes it in a form that favors oxygen release. Increased levels of 2,3-DPG, common in cases of chronic hypoxia (such as in high altitudes or chronic lung disease), significantly contribute to this rightward shift.

In contrast, increased pO2 does not induce a right shift in the dissociation curve. In fact, at higher partial pressures of oxygen, hemoglobin's affinity for oxygen tends to increase, which is contrary