Answer:
CO2 increases the affinity of oxygen for hemoglobin so that hemoglobin binds oxygen more strongly
Explanation:
Hemoglobin (Hb) is a protein found in red blood cells that functions to transport oxygen (O2) to the tissues. This protein has four subunits and each subunit binds to a heme group. Each heme group in Hb contains an iron atom that binds to one O2 molecule. The affinity of hemoglobin for O2 is a critical mechanism that is dependent on the ability of Hb to carry O2 molecules. Hb is fully saturated with O2 when all of its four O2-binding sites are occupied. Moreoever, the O2-hemoglobin dissociation curve is a plot of saturation of Hb regarding the partial pressure of O2 (PO2). A rightward shift in the curve indicates that Hb has a decreased affinity for O2, while a leftward shift in the curve indicates that Hb has an increased affinity for O2. As CO2 concentration increases, hemoglobin's affinity for O2 decreases, thereby Hb binds to O2 less tightly at heme group sites and therefore the dissociation curve shifts to the right.
