Question

certain blood vessels are lined by layers of tissue that ensure the vessels can expand in contractexercise is one known factor that can improve the function of these layers. Which of thefollowing is regulated because certain blood vessels are able to expand and contract?a. the removal of foreign substances from bloodb. the shape and size of red and white blood cellsc. the flow of blood from the heart to body tissuesd. the exchange of gases between blood and the air

Answer 1

The diameter of blood vessels changes when they contract or expand. When the blood vessels constrict and have a smaller diameter, the blood will have less room to flow and therefore the blood pressure will increase. While if the vessels expand, the blood pressure will decrease.

Therefore, blood flow is directly affected by the constriction or expansion of blood vessels, hence, the answer is c.