MEDICAL PHYSIOLOGY

Detailed explanation-1: -Binding of Oxygen to Hemoglobin: Oxygen Saturation (Dissociation) Curve. The hemoglobin molecule has four binding sites for oxygen molecules: the iron atoms in the four heme groups. Thus, each Hb tetramer can bind four oxygen molecules.

Detailed explanation-2: -Binding of oxygen to haem alters oxygen affinity by inducing structural changes in the adjacent globin chains. This molecular ‘co-operativity’ within haemoglobin is responsible for a sigmoidal-shaped oxygen dissociation curve and is influenced by pH, carbon dioxide, and 2, 3-diphosphoglycerate.