Typically, as an artery gets farther from the heart, its diameter decreases, and there is a(n)________.
A) decrease in the amount of smooth muscle and an increase in the number of elastic fibers
B) increase in the amount of smooth muscle and a decrease in the number of elastic fibers
C) increase in both smooth muscle and elastic fibers
D) decrease in both smooth muscle and elastic fibers
E) no change in the amount of smooth muscle or elastic fibers

Question

Quizplus · Accepted Answer

As arteries get farther from the heart, they experience less pulsatile pressure and need less elasticity to dampen pressure waves. Therefore, their diameter decreases, and smooth muscle becomes more important for maintaining vascular tone and regulating blood flow. The proportion of elastic fibers decreases while the amount of smooth muscle increases. Therefore, option B, an increase in the amount of smooth muscle and a decrease in the number of elastic fibers, is the best choice.

Typically, as an Artery Gets Farther from the Heart, Its