Cardiovascular System Flashcards
(17 cards)
CVS
transports O2 and nutrients throughout the body
removes CO2 and other waste products
atria
receiving chambers
ventricles
discharging chambers
atrioventricular (AV) valves
between the atria and ventricles
bicuspid - left
tricuspid - right
semilunar valves
between the ventricles and arteries
pulmonary semilunar valve
aortic semilunar valve
late diastole
both sets of chambers relax and ventricles fill passively
arteriole systole
atrial contraction forces a small amount of additional blood into ventricles
isovolumic ventricular contraction
first phase pushes AV valves closed but does not create enough pressure to open semilunar valves
ventricular ejection
ventricular pressure increases above arterial pressure and opens semilunar valves to eject blood
isovolumic ventricular relaxation
ventricles relax as pressure decreases, blood flows back into semilunar valve cusps and closes valves
angiotensin II
stimulates systemic vasoconstriction
promotes Na+ and H2O retention by inducing the release of aldosterone
angiotensin II
stimulates systemic vasoconstriction
promotes Na+ and H2O retention by inducing the release of aldosterone and ADH
activates thirst mechanism
reduces baroreflex to increase BP
cardiac output
amount of blood pumped by each side of the heart in one minute
CO = HR x SV
stroke volume
volume of blood pumped by each ventricle in one contraction
peripheral resistance
resistance = vessel length x blood viscosity / (vessel radius)^4
isotonic/dynamic exercise
muscle contraction of large muscle groups resulting in movement
increases CO, O2 consumption
decreases vascular resistance
volume load on heart
running, swimming
isometric/static exercise
constant muscle contraction of smaller muscle groups without movement
increases vascular resistance
minimal CO and O2 changes
pressure load on heart
weight lifting
