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the heart
test 1
Term | Definition |
---|---|
heart | 250-300 grams; located in the center of the thorax; all vessels, nerves, etc enter and leave the base (superior end) |
mediastinum | the heart, esophogus, and descending aorta |
outer layer of heart | epicardium, myocardium |
inner layer of heart | endocardium |
myocardium | cardiac muscle; intercalted discs; allow ions to jump from myocyte to myocyte |
pericardium | double layer; surrounds the heart |
serous pericardium | deep to the fibrous pericardium; visceral layer & parietal layer |
visceral layer | deep to the parietal layer; epicardium |
parietal layer | superficial to the visceral layer; attached to structures around it |
pericardial cavity | phospholipid lubricant to reduce friction around the heart |
fibrous pericardium | superficial to the serous pericardium |
pressure gradient | blood moves from high pressure to low pressure; only thing that moves blood |
valves of the heart | right atrioentricular valve; left atrioventricular valve; pulmonary valve; aortic valve; make sure blood flows in one direction |
systole | contraction of the heart |
diastole | relaxation of the heart |
cardiac cycle | one systole and one diastole |
heart rate | number of cardiac cycles per minute |
stroke volume | volume of blood ejected from a ventricle during a single systole; usually referring to the left ventricle |
cardiac output | volume of blood pumped by ventricle in one minute = (heart rate)(stroke volume) |
cardiac index | volume of blood pumped by a ventricle per minute per square meter of body surface = cardiac output/sq m of body surface |