ch 20 pt 4

Question 1

What is vasomotion?

Answer 1

Cycle of contracting and relaxing of precapillary sphincters

Question 2

At any time only what of body’s capillary beds are open

Answer 2

1/4

Question 3

What are venules?

Answer 3

Companion vessels with arterioles and merge to form veins

Question 4

Small and medium-sized veins

Answer 4

Companion vessels with muscular arteries

Question 5

Largest veins

Answer 5

Travel with elastic arteries

Question 6

Valves are made of

Answer 6

Tunica intima and elastic and collagen fibers

Question 7

At rest what percentage of blood is in systemic circulation

Answer 7

70%

Question 8

What is an end artery?

Answer 8

Is one that provides only one path for blood to reach an organ or region

Question 9

What is arterial anastomosis?

Answer 9

Two or more arteries converge to supply same region

Question 10

What is venous anastomosis?

Answer 10

Two or more veins drain same body region

Question 11

What is arteriovenous anastomosis?

Answer 11

Transports blood from artery directly to vein

Question 12

What is the portal system?

Answer 12

Artery -> capillary bed -> portal vein -> capillary bed -> vein

Question 13

What is the inverse for total cross-sectional area?

Answer 13

Blood flow velocity