The atrioventricular node (AV) is described as a knot of specialized cells located in which part of the heart?

The atrioventricular node (AV) is described as a knot of specialized cells located in which part of the heart?

• A. Left ventricle
• B. Apex of the heart
• C. Lower portion of the right atrium
• D. Interventricular septum

Answer: (C)

The atrioventricular node is part of the heart’s electrical conduction system and sits in the lower portion of the right atrium, on the interatrial septum near the tricuspid valve and the opening of the coronary sinus. Its location lets it receive the impulse from the atria and provide a brief delay before passing it to the ventricles via the bundle of His, coordinating timing for ventricular contraction. The other sites listed don’t house the AV node—the left ventricle and apex are in the left heart, and the interventricular septum is where the bundle of His travels, not where the AV node sits.

The atrioventricular node is part of the heart’s electrical conduction system and sits in the lower portion of the right atrium, on the interatrial septum near the tricuspid valve and the opening of the coronary sinus. Its location lets it receive the impulse from the atria and provide a brief delay before passing it to the ventricles via the bundle of His, coordinating timing for ventricular contraction. The other sites listed don’t house the AV node—the left ventricle and apex are in the left heart, and the interventricular septum is where the bundle of His travels, not where the AV node sits.