features of blood vessels

Question 1

elastic arteries - size

Answer 1

largest arteries in the body

Question 2

elastic arteries - tunica interna

Answer 2

well defined internal elastic lamina

Question 3

elastic arteries - tunica media

Answer 3

thick and dominated by elastic fibers; well defined external elastic lamina

Question 4

elastic arteries - tunica externa

Answer 4

thinner than tunica media

Question 5

elastic arteries - function

Answer 5

conduct blood from the heart to the muscular arteries

Question 6

muscular arteries - size

Answer 6

medium sized arteries

Question 7

muscular arteries - tunica interna

Answer 7

well defined internal elastic lamina

Question 8

muscular arteries - tunica media

Answer 8

thick and dominated by smooth muscle; thin external elastic lamina

Question 9

muscular arteries - tunica externa

Answer 9

thicker than tunica media

Question 10

muscular arteries - function

Answer 10

distribute blood to arterioles

Question 11

arterioles - size

Answer 11

microscopic

Question 12

arterioles - tunica interna

Answer 12

thin with a fenestrated internal elastic lamina that disappears distally

Question 13

arterioles - tunica media

Answer 13

1 or 2 layers of circularly oriented smooth muscle; distal-most smooth muscle cell forms a precapillary sphincter

Question 14

arterioles - tunica externa

Answer 14

loose collagenous connective tissue and symphathetic nerves

Question 15

arterioles - function

Answer 15

deliver blood to capillaries and help regulate blood flow to capillaries

Question 16

capillaries - size

Answer 16

microscopic, smallest blood vessel

Question 17

capillaries - tunica interna

Answer 17

endothelium and basement membrane

Question 18

capillaries - tunica media

Answer 18

none

Question 19

capillaries - tunica externa

Answer 19

none

Question 20

capillaries - function

Answer 20

permit exchange of nutrients and wastes between blood and interstitial fluid; distribute blood to - postcapillary venules

Question 21

postcapillary venules - size

Answer 21

microscopic

Question 22

postcapillary venules - tunica interna

Answer 22

endothelium and basement membrane

Question 23

postcapillary venules - tunica media

Answer 23

none

Question 24

postcapillary venules - tunica externa

Answer 24

sparse

Question 25

postcapillary venules - function

Answer 25

pass blood into muscular venules; permit exchange of nutrients and wastes between blood and interstitial fluid and function in white blood cell emigration

Question 26

muscular venules - size

Answer 26

microscopic

Question 27

muscular venules - tunica interna

Answer 27

endothelium and basement membrane

Question 28

muscular venules - tunica media

Answer 28

1 or 2 layers of circularly oriented smooth muscle

Question 29

muscular venules - tunica externa

Answer 29

sparse

Question 30

muscular venules - function

Answer 30

pass blood into veins; reservoirs for accumulating large volumes of blood (along with poastcapillary venules)

Question 31

veins - size

Answer 31

range from 0.5 mm to 2 cm in diameter

Question 32

veins - tunica interna

Answer 32

endothelium and basement membrane; no internal elastic lamina; contain valves; lumen is much larger than in accompanying artery

Question 33

veins - tunica media

Answer 33

much thinner than in arteries; no external elastic lamina

Question 34

veins - tunica externa

Answer 34

thickest of 3 layers

Question 35

veins - function

Answer 35

return blood to the heart; facilitated by valves in veins in limbs