19. The Blood Vessels

List three ways in which substances can cross the capillary wall.

The local control of blood flow due to the action of precapillary sphincters is:

(a) Vasomotion

(b) Autoregulation

(c) Selective resistance

(d) Turbulence

How is the anatomy of capillaries and capillary beds well suited to their function?

Large molecules such as peptides and proteins move into and out of the bloodstream by way of:

(a) Continuous capillaries

(b) Fenestrated capillaries

(c) Thoroughfare channels

(d) Venules

Which of the following best describes the microcirculatory flow of blood (microcirculation)?

Capillaries consist of:

a. Three thin tunics

b. Only a thin tunica intima with a well-developed internal elastic lamina

c. A thin sheet of endothelium with a basal lamina

d. Stratified epithelium

Which of the following correctly describes the flow of blood through a mesenteric capillary bed when the precapillary sphincters are constricted?

Which of the following areas of the body has the highest concentration of capillary beds?

Why do capillaries permit the diffusion of materials, whereas arteries and veins do not?

Which of the following structures is the 'leakiest'?

a. Continuous capillary

b. Sinusoidal capillary

c. Precapillary sphincter

d. Fenestrated capillary