Ch. 23: Circulatory System

Question 1

anastomosis

Answer 1

a convergence of two or more vessels

• veins do this with each other more than arteries do
• end arteries do not form these

Question 2

companion vessels

Answer 2

arteries and veins that lie next to each other

Question 3

tunica intima

Answer 3

endothelium: simple squamous epithelium and connective tissue
capillary walls contain only this

Question 4

tunica media

Answer 4

circularly arranged smooth muscle

Question 5

vasoconstriction

Answer 5

smooth muscle (tunica media) contraction

Question 6

tunica externa

Answer 6

outer connective tissue; anchors blood vessel to surroundings

Question 7

arteries

Answer 7

function = transport blood away from the heart

Question 8

elastic arteries

Answer 8

• largest arteries; branch into muscular arteries
• walls contain many elastic fibers
• most examples are near the heart (aorta, pulmonary & brachiocephalic arteries); fibers allow stretch when heart pumps blood to them

Question 9

elastic fibers

Answer 9

especially abundant in tunic media

Question 10

muscular arteries

Answer 10

• medium-sized arteries; branch into arterioles
• have a proportionately thicker tunica media with multiple layers of smooth muscle cells
• most named arteries are muscular (e.g., brachial artery)

Question 11

arterioles

Answer 11

• smallest arteries

- number of tunics and thickness of walls varies between longer & smaller ones

Question 12

capillaries

Answer 12

• smallest blood vessels (diameter only slightly larger than an erythrocyte)
• for most, consists solely of tunica intima
• allow metabolic exchange between blood & tissues

Question 13

capillary beds

Answer 13

formed by groups of capillaries, which perfuse organs and tissues throughout the body

Question 14

venules

Answer 14

• smallest veins, arising from merging capillaries
• companion vessels with arterioles
• merge to form veins

Question 15

veins

Answer 15

• drain capillaries and return blood to the heart
• pressure is much lower here than in arteries
• @ rest, hold about 60% of the body’s blood

Question 16

60

Answer 16

at rest, veins hold about ___% of the body’s blood

Question 17

small, medium

Answer 17

________ and _________ size veins travel with muscular arteries

Question 18

large

Answer 18

_________ size veins travel with elastic arteries

Question 19

valves

Answer 19

most veins contain _________ to prevent pooling of blood; formed from tunica intima

Question 20

blood pressure

Answer 20

the force per unit area the blood places on the inside of a blood vessel

Question 21

sphygmomanometer

Answer 21

measures blood pressure

Question 22

pulsatile

Answer 22

pressure is _________ until reaches capillaries

Question 23

decreases

Answer 23

pressure _________ from aorta venue cavae

Question 24

hypertension

Answer 24

high blood pressure - persistent blood pressure of 140/90 or greater

Question 25

hypertension

Answer 25

high blood pressure - persistent blood pressure of 140/90 or greater "silent killer" - damaging effects may take many years to be clinically apparent

Question 26

hypertension-related diseases

Answer 26

include heart failure, stroke, heart attack, kidney failure

Question 27

avoiding hypertension

Answer 27

do this by eating a heart-healthy diet, maintaining a healthy weight, exercising regularly, avoiding high-stress situations, avoid drinking or smoking excessively

Question 28

venous return

Answer 28

skeletal muscle pump & respiratory pump are factors that influence _________ _________

Question 29

more

Answer 29

artery lumens are __(more/less)__ narrow than vein lumens

Question 30

more

Answer 30

artery walls are __(more/less)__ thick than companion vein walls

Question 31

more

Answer 31

artery walls have __(more/less)__ elastic and collagen fibers in tunics than veins

Question 32

systemic arteries and pulmonary veins

Answer 32

transport blood high in oxygen and low in carbon dioxide

Question 33

pulmonary arteries and systemic veins

Answer 33

transport blood low in oxygen and high in carbon dioxide

Question 34

placenta

Answer 34

fetus receives oxygen and nutrients through the _________

Question 35

umbilical vein

Answer 35

placental blood is delivered to the fetus by the _________ _________

Question 36

foramen ovale

Answer 36

placental blood delivered to fetus by umbilical vein, then travels to the right atrium -most blood then shunted to the left atrium via _________ _________; this blood then goes to the left ventricle, then to the aorta

Question 37

ductus arteriosus

Answer 37

after blood goes through foramen oval to left ventricle and then aorta, some blood enter right ventricle and pulmonary trunk; most of this blood goes through _________ _________ to aorta

Question 38

umbilical arteries

Answer 38

deoxygenated blood returns to placenta through _________ _________

Question 39

deep vein thrombosis

Answer 39

clots develop in the veins of the lower limbs - clots commonly travel to and block a pulmonary artery - caused by inactivity, so seen very frequently in bedridden patients - treatment: anti-clotting drugs

Question 40

pulmonary embolism

Answer 40

when clots travel to and block a pulmonary artery; common in deep vein thrombosis

Question 41

varicose veins

Answer 41

occur when the valves in the veins weaken and fail - back flow is not prevented, so blood tends to pool in the veins - can be hereditary or caused by obesity - treatment: lasar therapy

Question 42

aneurysm

Answer 42

extreme dilation of a blood vessel - wall becomes very thin, putting it at risk of rupturing - frequent causes include hypertension or arteriosclerosis - most common in abdominal aorta, as well as vessels to the brain and kidneys