In the lup-dup sound of a beating heart,which of the following make the first heart sound?
A) closing of the atrioventricular valves
B) closing of the pulmonary valve
C) closing of the aortic valve
D) the contraction of the left ventricle
E) the contraction of the right ventricle

Question

Quizplus · Accepted Answer

The first heart sound is caused by the closure of the atrioventricular valves (the tricuspid valve on the right and the mitral valve on the left) during ventricular contraction.

In the Lup-Dup Sound of a Beating Heart,which of the Following