GENERAL ANATOMY
ANATOMY OF THE HEART
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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the AV valves open.
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the AV valves close.
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the atria contract.
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the semilunar valves close.
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Detailed explanation-1: -The second heart sound (S2) is produced by the closure of the aortic (A2) and the pulmonary valves (P2) at the end of systole.
Detailed explanation-2: -The second heart sound (S2) represents closure of the semilunar (aortic and pulmonary) valves (point d). S2 is normally split because the aortic valve (A2) closes before the pulmonary valve (P2). The closing pressure (the diastolic arterial pressure) on the left is 80 mmHg as compared to only 10 mmHg on the right.
Detailed explanation-3: -S2. The second heart sound, called S2, makes a “dub” sound caused by the closure of the semilunar (aortic and pulmonary) valves following ventricular systole.
Detailed explanation-4: -The vibrations of the second heart sound occur at the end of ventricular contraction and identify the onset of ventricular diastole and the end of mechanical systole.
Detailed explanation-5: -The second sound (S2) is made of two component sounds: Aortic valve closure (A2) which happens first. Pulmonic valve closure (P2) which happens second. A2 is heard widely all over the chest.