Each Cardiac Cycle Begins with _______

Question

Each cardiac cycle begins with _______.
A) contraction of the atria
B) diastole
C) contraction of the ventricles
D) closure of the semilunar valves

Accepted Answer

The cardiac cycle begins with the contraction of the atria, which is known as atrial systole. This helps to fill the ventricles with blood before they contract.