All of the following are physiologic adaptations the body makes when a slow drop in the number of red cells occurs except:

a. Erythropoietin level increases.
b. Oxygen dissociation curve shifts to left.
c. Cardiac output increases.
d. Respiratory rate increases.

ANS: B
When anemia develops, the concentration of 2,3-biphosphoglycerate (2,3-BPG) increases. This causes a shift to the right in the oxygen dissociation curve, which results in more effective delivery of oxygen to tissue (oxygen affinity of hemoglobin decreases).