Question

Describe what is happening during the phase of the cardiac action potential labeled 2 in the diagram.

a) Depolarization of the atria
b) Depolarization of the ventricles
c) Repolarization of the atria
d) Repolarization of the ventricles

Answer 1

Phase 2 of the cardiac action potential, labeled d) atrial repolarization or ventricular repolarization, describes the process of the ventricles relaxing and returning to their resting state after depolarization.

Step-by-step explanation:

During phase 2 of the cardiac action potential, labeled d) atrial repolarization or ventricular repolarization, the ventricles begin to relax and undergo repolarization. This means that the electrical charge within the ventricles is returning to its resting state after depolarization, preparing for the next cardiac cycle. Repolarization is marked by the T wave on an electrocardiogram (ECG).