Question

Explain how different factors influence the hemoglobin binding curve, and how they affect the transition between the T and the R state. Also explain the physiological consequences of shifting the hemoglobin binding curve to higher affinity or lower affinity.

Answer 1

There are several important factors that affect the affinity of hemoglobin to oxygen and it includes pH, temperature, carbon dioxide, 2,3-BPG and carbon monoxide. By increasing the hydrogen ion concentration, the temperature, the carbon dioxide concentration or the amount of 2,3-BPG present in the red blood cell, we ultimately decrease the affinity of hemoglobin to oxygen and therefore shift the curve to the right side. This allows us to unload more oxygen to our tissues. On the other hand, by increasing the concentration of carbon monoxide, we actually increase the affinity of hemoglobin for oxygen and we therefore shift the curve to the left side. This means that less oxygen will actually be delivered to our tissues. decrease in pH shifts the standard curve to the right, while an increase shifts it to the left.