What is the correct sequence of components of the cardiac conduction system?

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

Answer: (A)

Verified step by step guidance

1. Understand the function of the cardiac conduction system: It is responsible for initiating and coordinating the contraction of the heart muscle.
2. Identify the primary pacemaker of the heart: The Sinoatrial (SA) node, located in the right atrium, initiates the electrical impulse.
3. Trace the pathway of the electrical impulse: From the SA node, the impulse travels to the Atrioventricular (AV) node, which is located at the junction between the atria and ventricles.
4. Follow the impulse through the Bundle of His: After the AV node, the impulse travels down the Bundle of His, which is a pathway that conducts the impulse to the ventricles.
5. Conclude with the Purkinje fibers: The impulse finally spreads through the Purkinje fibers, which distribute the electrical signal throughout the ventricles, causing them to contract.