Systole occurs when
A) the heart tissue is contracting.
B) the heart tissue is relaxing.
C) the semilunar valves open and close.
D) the aortic valves open and close.
E) there is no heartbeat.

Question

Quizplus · Accepted Answer

Systole is the contraction phase of the cardiac cycle during which blood is pumped out of the heart. Therefore, choice A is the correct answer as it describes the heart tissue contracting during systole.

Systole Occurs When