Answer :
Answer:
QRS represents ventricular depolarization. This depolarization initiates ventricular contraction which closes the mitral and tricuspid valves. It is the closure that is heard as the first heart sound.
Explanation:
Answer:
QRS represents ventricular depolarization. This depolarization initiates ventricular contraction which closes the mitral and tricuspid valves. It is the closure that is heard as the first heart sound.
Explanation: