Chapter 13: Blood Vessels and Circulation

Question 1

three layers of blood vessels

Answer 1

tunica intima, tunica media, tunica externa

Question 2

tunica intima

Answer 2

tunica internainnermost layer of a blood vessel; endothelial lining and connective tissue (mostly elastic fibers)

Question 3

tunica media

Answer 3

middle layer; contains smooth muscle

Question 4

tunica adventitia

Answer 4

tunica externaforms a sheath of connective tissue around the vessel

Question 5

elastic arteries

Answer 5

large arteries with wide diameters up to 2.5 cm; extremely resilient

Question 6

muscular arteries

Answer 6

“medium-sized” or “distribution” arteriesdelivers blood to skeletal muscles and internal organs; diameter of approximately .4 cm

Question 7

capillaries

Answer 7

only blood vessels whose walls permit exchange between blood and surrounding interstitial fluid; diameter is very close to that of a single RBChave biggest impact on blood pressure

Question 8

precapillary sphincter

Answer 8

band of smooth muscle that adjusts the blood flow into each capillary

Question 9

vasomotion

Answer 9

cyclical changes in diameter of the blood vessel brought about by precapillary sphincter

Question 10

anastomosis

Answer 10

joining of two blood vessels

Question 11

valves

Answer 11

prevent back flow of blood in veins

Question 12

factors that affect bloodflow

Answer 12

pressure and resistance

Question 13

peripheral resistance

Answer 13

total resistance of arterial system; sources include vascular resistance, viscosity, and turbulence

Question 14

vascular resistance

Answer 14

the resistance of the blood vessels to blood flowmost important factor is friction

Question 15

viscosity

Answer 15

resistance to flow that results from interactions among molecules in a liquidlow viscosity flows easily; high viscosity = thick, syrupy liquids that do not flow easilyblood has viscosity about 5x that of water

Question 16

anemia

Answer 16

hematocrit is reduced due to inadequate production of hemoglobin

Question 17

systolic pressure

Answer 17

the peak pressure measured during ventricular systole

Question 18

diastolic pressure

Answer 18

minimum pressure measured during ventricular diastole

Question 19

pulse pressure

Answer 19

difference between systolic and diastolic pressure

Question 20

capillary hydrostatic pressure

Answer 20

pushes water out of capillary when CHP>BOP33mmHg at arteriolar end; 18mmHg at venous end

Question 21

blood osmotic pressure

Answer 21

pulls water into capillary when BOP>CHP

Question 22

2 factors that help venous blood overcome gravity and return to heart

Answer 22

muscular compression, respiratory pump

Question 23

3 mechanisms or cardiovascular function

Answer 23

autoregulation, neural mechanisms, endocrine mechanisms

Question 24

baroreceptors

Answer 24

monitor blood pressure within aortic and carotid sinuses

Question 25

chemoreceptors

Answer 25

monitor CO2, O2, and pH in blood and CSFcarotid and aortic bodies

Question 26

antidiuretic hormone (ADH)

Answer 26

released at posterior pituitary gland in response to a decrease in blood volume, increase in osmotic concentration of blood, or in response to angiotensin IIwater-conserving effect, peripheral vasoconstriction

Question 27

angiotensin II

Answer 27

formed in blood following release of renin by kidneystimulates cardiac output, triggers arteriole constriction, stimulates thirst, stimulates secretion of ADH and aldosterone

Question 28

Erythropoietin

Answer 28

released by kidneys when blood pressure falls or when blood oxygen is lowsimulates red blood cell production

Question 29

Atrial natriuretic peptide (ANP)

Answer 29

released by heart in response to too much bloodreduces blood volume by increasing loss of sodium ions and water at kidneys, reducing thirst, blocking release of ADH/aldosterone, and stimulating peripheral vasodilation

Question 30

venous reserve

Answer 30

Large reservoirs of slowly moving venous blood in the liver, bone marrow, and skin

Question 31

cystic medial necrosis

Answer 31

degenerative disease of connective tissue commonly associated with hypertension and aging; can cause dissecting aneurysms

Question 32

aortic arch

Answer 32

left subclavian/left common carotid branch directlybrachiocephalic trunk comes off of aorta before branching into right subclavian/right common carotid

Question 33

great saphenous vein

Answer 33

longest vein in body; drains blood from foot, leg, and thigh; joins with femoral vein

Question 34

umbilical cord

Answer 34

2 arteries and 1 vein

Question 35

foramen ovale

Answer 35

interatrial opening during development

Question 36

ductus arteriosus

Answer 36

becomes ligamentum arteriosuma blood vessel in a fetus that bypasses pulmonary circulation by connecting the pulmonary artery directly to the ascending aorta

Question 37

thrombus

Answer 37

stationary blood clot

Question 38

orthostatic hypotension

Answer 38

low blood pressure that occurs upon standing up

Question 39

phlebitis

Answer 39

inflammation of a vein

Question 40

varicose veins

Answer 40

sagging, swollen veins distorted by gravity and by the failure of the venous valves

Question 41

right atrium

Answer 41

average pressure is 2mmHg

Question 42

Korotkoff sounds

Answer 42

the sound heard as the pressure in the cuff falls below the systolic pressure

Question 43

afferent vessels

Answer 43

veins

Question 44

efferent vessels

Answer 44

arteries

Question 45

beta 2 receptors

Answer 45

arteriole dilation