ANATOMY
CHEST AND CARDIOVASCULAR
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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the atria contract (atrial systole) and push blood into the ventricles; then, as the atria start to relax, the ventricles contract (ventricular systole) and pump blood out of the heart
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phase of the heartbeat when the heart muscle relaxes and allows the chambers to fill with blood.
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Either A or B
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None of the above
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Detailed explanation-1: -Diastole begins with the closing of the aortic valve (or pulmonic) and ends with the closing of the mitral valve (or tricuspid). This period encompasses the ventricular relaxation and filling. Diastole represents when the blood vessels return blood to the heart in preparation for the next ventricular contraction.
Detailed explanation-2: -The cardiac cycle refers to the alternating contraction and relaxation of the myocardium in the walls of the heart chambers, coordinated by the conduction system, during one heartbeat. Systole is the contraction phase of the cardiac cycle, and diastole is the relaxation phase.
Detailed explanation-3: -diastole, in the cardiac cycle, period of relaxation of the heart muscle, accompanied by the filling of the chambers with blood. Diastole is followed in the cardiac cycle by a period of contraction, or systole (q.v.), of the heart muscle.