What is the function of the cardiac conduction system?

• A. It pumps blood through the lungs
• B. It filters blood in the heart
• C. It coordinates electrical impulses to synchronize contractions
• D. It generates and conducts electrical impulses that coordinate heartbeats (SA node, AV node, Bundle of His, Purkinje fibers)

Answer: (D)

The function of the cardiac conduction system is to generate and propagate electrical impulses that coordinate the timing and sequence of heart muscle contractions. The SA node acts as the natural pacemaker, sending out regular impulses. These travel to the AV node, which introduces a short delay so the atria can contract and fill the ventricles. The impulse then moves through the Bundle of His to the Purkinje fibers, rapidly depolarizing the ventricles so they contract in a synchronized, efficient manner. This system sets the heart’s rhythm and ensures the atria squeeze first, followed by the ventricles, producing coordinated pumping. Other options describe mechanical pumping or other processes, which are not the conduction system’s role.