unit d circulatory system Flashcards
what are the chordae tendineae? what do they do?
“the heart strings”
thin, very strong
inelastic fibrous cords that extend from the atrioventricular valves (the tricuspid and mitral valves) to the muscles within the right and left ventricles
what causes the sound of a heartbeat?
“lubb” (first, louder) - the closing of the AV valves
“dubb” (second, softer) - the closing of the semilunar valves
what is cardiac output
the amount of blood pumped by each of the ventricles per minute
what is stroke volume
the amount of blood ejected by each ventricle per beat
how do cardiac output, heart rate and blood pressure affect each other
increased heart rate causes increased cardiac output which results in higher blood pressure
what is arteriole resistance
constriction of arterioles, causes decrease in blood flow and lower blood pressure
what happens during hypothermia
- decreased blood flow and/or skin temperature
- impulses go to hypothalamus
3.
what can we not see during a heart dissection
purkinje fibres
bicuspid valve
between left ventricle and left atrium
name given to the vessels given between the arteries and capillaries
arterioles
blood cells that make up 44% of the cells in our blood and have no nucleus
red blood cells
what is an aneurysm
an artery’s wall weakens and causes an abnormally large bulge
the amount of blood that flows through the heart in one minute
cardiac output
in a capillary this happens when the fluid pressure is greater than the osmotic pressure
filtration
120/80
the top number in this blood pressure reading represents…
systolic blood pressure
