Where is blood flow slowest, and what contributes to the diminished velocity?
A) Flow is slowest in the capillaries because of their larger cross-sectional area and narrow diameter.
B) Large veins have the slowest blood flow because they receive blood from several different medium-sized veins and they have valves that interfere with blood flow.
C) Arteriole blood flow is slowest because they are farthest from the heart and are the narrowest arteries.
D) Distributing arteries of the brain have the slowest flow of blood because they have a large cross-sectional area and many branches.

Question

Quizplus · Accepted Answer

Blood flow is slowest in the capillaries because they have a much larger total cross-sectional area than larger vessels such as arteries and veins. The narrow diameter of capillaries also contributes to slower blood flow, as it creates significant resistance to blood flow. This slower flow allows for exchange of nutrients and waste products between the bloodstream and tissues.

Where Is Blood Flow Slowest, and What Contributes to the Diminished