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Likurg_2 [28]
3 years ago
10

The opening and closing of the heart valves is caused by

Biology
1 answer:
Rashid [163]3 years ago
3 0

Answer:

pressure changes of alternating contraction and relaxation during the cardiac cycle.

Explanation:

Opening and closing of heart valves are regulated by changes in the blood pressure of various heart chambers during the cardiac cycle. During atrial systole, the higher blood pressure in the atria opens both AV valves and forces the blood to enter the ventricles. The semilunar valves are closed. During ventricular systole, the higher blood pressure in the ventricles opens both semilunar valves to allow the blood to enter the pulmonary trunk and aorta. At this time, both  the atrioventricular valves are closed.

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Gre4nikov [31]

Answer:

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