The Exchange of Oxygen and Carbon Dioxide in the Cardiovascular

Question

The exchange of oxygen and carbon dioxide in the cardiovascular system occurs in which vessels?
A) veins
B) arteries
C) capillaries
D) venules
E) arterioles

Accepted Answer

Capillaries are the smallest and narrowest vessels in the cardiovascular system, where exchange of gases (oxygen and carbon dioxide) takes place between the bloodstream and the surrounding tissues. Oxygen from the capillaries diffuses into the cells, while carbon dioxide generated by cellular respiration moves into the bloodstream to be transported to the lungs for elimination. Thus, capillaries are known as the sites of gas exchange in the cardiovascular system.