Answer to Question #103349 in Human Anatomy and Physiology for Nibedita Rudra

Question

Compare the oxygen dissociation curves of haemoglobin and myoglobin.

Answer 1

The oxygen dissociation curve for hemoglobin has a sigmoid shape because of the co-operative binding of oxygen to the 4 polypeptide chains. On the other hand, Myoglobin is made up of a single polypeptide with only one heme group and hence is not capable of cooperative binding. Thus the oxygen dissociation curve is not sigmoid but it is a hyperbola.