Which phase of the heartbeat is the heart contracting?

• A. Movement of blood
• B. Systole
• C. Cardiac Conduction System
• D. Myogenic

Answer: (B)

The main idea is understanding what each term refers to in the heartbeat cycle. Systole is the contraction phase of the heart; during systole the heart muscle tightens, raising pressure and pushing blood out of the chambers into the arteries. That makes it the specific phase in which the heart is actively contracting.

The other terms aren’t phases of contraction. “Movement of blood” describes what happens as a result of the heartbeat, not the contraction phase itself. The cardiac conduction system is the network that generates and coordinates the electrical impulses that trigger contraction. And “myogenic” describes the heart’s ability to generate rhythmic contractions on its own, not the contraction phase per se.