What is the correct sequence of events in the transmission of an impulse through the heart muscle?

• A. Atrioventricular node, Sinoatrial node, Purkinje fibers, Bundle of His
• B. Bundle of His, Purkinje fibers, Atrioventricular node, Sinoatrial node
• C. Sinoatrial node, Atrioventricular node, Bundle of His, Purkinje fibers
• D. Purkinje fibers, Bundle of His, Sinoatrial node, Atrioventricular node

Answer: (C)

Verified step by step guidance

1. Begin by understanding the role of each component in the heart's conduction system. The Sinoatrial (SA) node is the heart's natural pacemaker, initiating the electrical impulse.
2. The impulse travels from the SA node to the Atrioventricular (AV) node. The AV node acts as a gatekeeper, slowing down the impulse before it moves to the ventricles, allowing the atria to contract and fill the ventricles with blood.
3. Next, the impulse moves from the AV node to the Bundle of His. The Bundle of His is a pathway that transmits the impulse from the AV node to the ventricles.
4. The impulse then travels through the Bundle of His to the Purkinje fibers. These fibers distribute the impulse throughout the ventricles, causing them to contract and pump blood to the lungs and the rest of the body.
5. Review the sequence: Sinoatrial node -> Atrioventricular node -> Bundle of His -> Purkinje fibers. This is the correct order of impulse transmission through the heart muscle.