Trace the wave of depolarization through the heart.

Question

Quizplus · Accepted Answer

The SA node generates the electrical signal that initiates the heartbeat, causing the atria to depolarize and contract. The signal then travels to the AV node, which acts as a gatekeeper, delaying the impulse slightly to allow the ventricles to fill with blood before contracting. The impulse then travels through the bundle of His and into the Purkinje fibers, rapidly spreading the signal to the ventricles, causing them to contract. Therefore, the correct order of depolarization is SA node → atria → AV node → bundle of His → Purkinje fibers → ventricles, which is only represented in option D.

Trace the Wave of Depolarization Through the Heart