Biology: The Cardiac Cycle Flashcards
What happens during atrial systole?
-ventricles relax, atria contract -volume decrease, pressure increase -atrioventricular valves fully open -blood pushed into ventricles
What happens during ventricular systole?
-ventricles contract, atria relax -volume decrease, pressure increase -atrioventricular valves close -semilunar valves forced open -blood pumped through arteries
What occurs during diastole of the cardiac cycle?
-atria and ventricles relax -arterial pressure lower than veins -semilunar valves close -blood enters atria from veins -atria pressure exceeds ventricular pressure -atrioventricular valves open slightly -blood into ventricles passively -cycle restarts
What is one heartbeat equal to?
time it takes for one complete cardiac cycle
What equation is used to calculate cardiac output?
cardiac output (cm3min-1) = stroke volume (cm3/beat) x heart rate (bpm)