Blood in a Capillary Leaving a Nearby Cell Would Contain

Question

Blood in a capillary leaving a nearby cell would contain
A)a lower concentration of carbon dioxide than when it arrived.
B)a higher concentration of carbon dioxide than when it arrived.
C)a higher concentration of oxygen than when it arrived.
D)less hemoglobin than when it arrived.

Accepted Answer

Capillaries are the site of gas exchange between the blood and nearby cells. When blood enters a capillary, it has a high concentration of oxygen and a low concentration of carbon dioxide. As it passes by nearby cells, the cells take up the oxygen and release carbon dioxide into the blood. Therefore, the blood leaving the capillary near the cells will have a lower concentration of oxygen and a higher concentration of carbon dioxide than when it arrived.