heart valve
A heart valve controls the direction of blood flow through the heart by opening and closing with each heartbeat. The four valves in the heart are the tricuspid valve, pulmonary valve, mitral valve and aortic valve.
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A heart valve controls the direction of blood flow through the heart by opening and closing with each heartbeat. The four valves in the heart are the tricuspid valve, pulmonary valve, mitral valve and aortic valve.
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