Hemoglobin (Hb) in the blood absorbs oxygen to form oxyhemoglobin [Hb(O2)2], which transports oxygen to the cells. The equilibrium can be generally represented by the following
(though it is actually composed of a series of equilibria in which Hb binds from between 1 and 4 O2 molecules per unit depending on the partial pressure of O2.) The cells consume oxygen, producing water and CO2 as a result of cellular respiration. While de-oxyhemoglobin has alower affinity for CO2 than for O2 it transports CO2 from the tissues back to the lungs. In addition, Hb has a much higher affinity for CO than for O2.
Hb + 2O2(gas) <==> Hb(O2)2
Normal blood pH is about 7.4. Under metabolic stress a situation known as acidosis can result in which the pH of the blood drops. This results in a shift of the above equilibrium to the left. Give an explanation for each of the following observations based upon the principles of equilibrium.
(a) Free hemoglobin readily picks up O2 in the lungs
(B) Oxyhemoglobin releases O2 to the tissues
(C.) A person is hyperventilating, his/her dissolved CO2 levels rise in the blood, what effect will this have on O2 transport to the tissues? Why?