Question

Arterioles

A. Have a smaller wall:lumen ratio than have arteries.

B. Play a major role in regulating arterial blood pressure.

C. Play a major role in regulating local blood flow.

D. Offer more resistance to flow than capillaries.

E. Have a larger total cross-sectional area than do the capillaries.

Answer 1

A. False In arterioles the ratio is much greater, at about 1:1.

B. True They provide most of the peripheral resistance.

C. True Local flow varies directly with the fourth power of their radii.

D. True The drop in pressure across arterioles is greater than that across capillaries.

E. False It is smaller, so blood flow velocity is higher in arterioles.