The P Wave of the Electrocardiogram is a Signal From

Question

The P wave of the electrocardiogram is a signal from
A) the SA node.
B) depolarization of the AV node.
C) depolarization of the atria.
D) repolarization of the atria.
E) depolarization of the ventricles.

Accepted Answer

The P wave on an electrocardiogram corresponds to the depolarization of the atria, specifically the spread of electrical activity from the sinoatrial (SA) node throughout the atria. The SA node is the natural pacemaker of the heart and initiates the electrical impulses that cause the atria to contract.