Cardiovascular System

Question 1

cardiovascular system

Answer 1

left atrium and left ventricle
aorta
arteries
arterioles
capillaries
venules
veins
inferior/superior vena cava
right atrium and right ventricle
pulmonary artery
alveolar capillary network
pulmonary vein

Question 2

tunica intima (inner layer)

Answer 2

consists of endothelial cells, connective tissue, and a basal layer of elastic tissue that separates the tunica intima from the tunica media

Question 3

tunica media (middle layer)

Answer 3

characterized by the presence of layers of vascular smooth muscle cells and an elastin-rich extracellular matrix

Question 4

tunica adventitia (outer layer)

Answer 4

consists primarily of fibroblasts, collagen, and nerve endings and is critical in the regulation of the dynamic lumen size

Question 5

arterial tree

Answer 5

there are changes in the structural makeup of arteries throughout the arterial tree which is critical for organ perfusion and the delivery of nutrients to metabolically active tissues

Question 6

conducting (elastic) arteries

Answer 6

characterized by layers of elastic fibers to adequately stretch to accommodate the blood surge with each ventricle contraction

Question 7

conduit (muscular) arteries

Answer 7

characterized by many smooth muscle cells for adequate vasodilation and vasoconstriction to occur for blood delivery as needed

Question 8

arterioles

Answer 8

consists of a tunica media that has no more than six rings of smooth muscle and a tunica adventitia that is similar in size

Question 9

blood flow through the arteries is regulated by

Answer 9

blood pressure which is the pressure of circulating blood on the walls of blood vessels

Question 10

maintenance of normal blood pressure is dependent on

Answer 10

the balance between cardiac output and peripheral vascular resistance

Question 11

systolic blood pressure

Answer 11

indicates how much pressure your blood is exerting against your artery walls when the heart contracts
first Korotkoff sound

Question 12

diastolic blood pressure

Answer 12

indicates how much pressure your blood is exerting against your artery walls while the heart is resting between beats
fifth Korotkoff sound

Question 13

conducting and conduit arteries

Answer 13

have the highest blood pressure
thicker and more elastic to accommodate the higher pressure

Question 14

arterioles

Answer 14

have a lower blood pressure

Question 15

blood pressure regulation

Answer 15

autonomic nervous system:
vasoconstriction (increase BP)
increase in sympathetic input (epinephrine and norepinephrine)
vasodilation (decrease BP)
increase in parasympathetic (acetylcholine)
decrease in sympathetic input (epinephrine and norepinephrine)

Question 16

renin-angiotensin-aldosterone system

Answer 16

nitric oxide
synthesized in response to shear stress by endothelial cells from arginine
attenuates sympathetic nervous system vasoconstriction to vasodilation to decreased blood pressure

Question 17

hypertension

Answer 17

a condition in which the force against the artery wall is too high

Question 18

primary hypertension

Answer 18

no identifiable cause of high blood pressure but tends to develop gradually over many years
accounts for 90-95% of hypertension cases

Question 19

secondary hypertension

Answer 19

high blood pressure caused by an underlying condition which tends to appear suddenly
underlying conditions: obstructive sleep apnea, adrenal gland tumors, kidney disease, thyroid problems, congenital vascular defects, prescriptions drugs, illegal drugs

Question 20

the development of hypertension is complex because of

Answer 20

the multiplicity of causal factors potentially implicated in its pathophysiology, including genetic, environmental, lifestyle, and metabolic factors as well as physiological vascular ageing

Question 21

sympathetic over-activity causes damage to the vascular wall

Answer 21

increased collagen and decreased elastin result in increased vascular stiffness (increased blood pressure)
less elastic vessels cause the left ventricle to work harder to supply enough blood to the body

Question 22

inappropriate activation of the renin-angiotensin system

Answer 22

increase in sodium and water reabsorption at the kidney when not necessary causing an increase in blood pressure

Question 23

endothelial damage

Answer 23

increased blood pressure and therefore shear stress (friction) causes damage to the tunica intima
impaired secretion and/or activity of local vasodilating metabolites

Question 24

capillaries

Answer 24

humans have about 2000-3000 capillaries per square millimeter of tissue
contains 6% of total blood volume
blood flow velocity relates inversely to cross sectional area

Question 25

precapillary sphincters control blood flow into a specific capillary to meet metabolic requirements

Answer 25

at rest 1 of every 30-40 capillaries in skeletal muscle remains open

Question 26

factors influencing relaxation of precapillary sphincter

Answer 26

increased blood pressure
intrinsic neural control
local metabolites produced during exercise

Question 27

systemic venous vessels

Answer 27

serve as blood reservoirs as they contain 65% of total blood volume at rest

Question 28

blood pressure declines in direct proportion to the resistance it encounters in the vascular circuit

Answer 28

venous return is therefore only possible because of valves

Question 29

skeletal muscle pump

Answer 29

rhythmic action of muscular activity and consequent compression of thin veins contributes to venous return

Question 30

active recovery cool-down

Answer 30

facilitates blood flow via skeletal muscle contraction through the venous system back to the heart

Question 31

increased skeletal muscle blood flow by dilation

Answer 31

skeletal muscle blood flow closely couples to metabolic demands

Question 32

open dormant capillaries

Answer 32

increase total muscle blood flow
deliver large blood volume with minimal increase in blood flow velocity
increase surface for gas and nutrient exchange

Question 33

reduced blood flow to non-active tissue

Answer 33

increased sympathetic nervous system outflow
local chemicals that stimulate vasoconstriction