Normal heart sounds are caused by which of the following events?
A) excitation of the SA node
B) closure of the heart valves
C) friction of blood against the chamber walls
D) opening and closing of the heart valves

Question

Quizplus · Accepted Answer

Normal heart sounds are primarily caused by the closure of the heart valves, specifically the atrioventricular valves (producing the first heart sound, S1) and the semilunar valves (producing the second heart sound, S2).

Normal Heart Sounds Are Caused by Which of the Following