The erythrocyte (red blood cell)count increases after a while when an individual goes from a low to a high altitude because the ________.
A) basal metabolic rate is higher at high altitudes
B) concentration of oxygen and/or total atmospheric pressure is lower at high altitudes
C) concentration of oxygen and/or total atmospheric pressure is higher at higher altitudes
D) temperature is lower at higher altitudes

Question

Quizplus · Accepted Answer

At high altitudes, the concentration of oxygen in the atmosphere decreases, leading to hypoxia (lack of oxygen) which triggers the production of erythrocytes to compensate for the decreased oxygen carrying capacity in the blood. The total atmospheric pressure also decreases at high altitudes, but this alone does not cause an increase in erythrocyte count. The basal metabolic rate may increase at high altitudes to compensate for hypoxia, but this is not the main cause for the increase in erythrocyte count. Temperature changes at altitude may affect erythrocyte count indirectly by affecting other physiological responses, but direct effects on erythrocyte count have not been reported.

The Erythrocyte (Red Blood Cell)count Increases After a While When