At a capillary bed, a vasoconstrictor
A) constricts local arterioles, thereby increasing pressure and increasing local blood flow.
B) stimulates precapillary sphincters and decreases local blood flow.
C) dilates local arterioles, thereby increasing pressure and increasing local blood flow.
D) inhibits precapillary sphincters to relax and decreases local blood flow.
E) constricts precapillary sphincters and thereby increases local blood flow.

Question

Quizplus · Accepted Answer

A vasoconstrictor stimulates precapillary sphincters to constrict, which decreases local blood flow by reducing the diameter of the blood vessels, thus limiting blood flow into the capillary bed.

At a Capillary Bed, a Vasoconstrictor