Conduction System

What is the primary function of the SA node?

• It records the heart's electrical activity.

• It serves as the heart's natural pacemaker.

• It conducts impulses to the apex of the heart.

• It delays electrical impulses to the ventricles.

Where is the AV node located?

• Within the ventricular myocardium.

• At the apex of the heart.

• On the other side of the right atrium, near the AV valve.

• Near the entrance of the superior vena cava.

Which component of the cardiac conduction system serves as the electrical gateway to the ventricles?

• SA node

• AV node

• Purkinje fibers

• Bundle of His

What is the primary purpose of the delay caused by the AV node?

• To initiate the heartbeat.

• To synchronize the heartbeat with the respiratory rate.

• To allow the ventricles to fill with blood before they contract.

• To ensure the atria contract before the ventricles.

What is the role of the AV bundle?

• To initiate the heartbeat.

• To repolarize the ventricles.

• To delay electrical impulses.

• To conduct impulses to the bundle branches.

How do Purkinje fibers contribute to the heart's function?

• By acting as the heart's natural pacemaker.

• By delaying electrical impulses to the ventricles.

• By spreading impulses throughout the ventricular myocardium.

• By recording the heart's electrical activity.

What does the P wave on an ECG represent?

• Ventricular depolarization.

• Atrial depolarization.

• Ventricular repolarization.

• The delay of electrical impulses at the AV node.

What event does the QRS complex on an ECG mark?

• The firing of the SA node.

• Ventricular relaxation.

• Atrial repolarization.

• The firing of the AV node and ventricular depolarization.

What is the significance of the S-T segment on an ECG?

• It marks the delay of electrical impulses at the AV node.

• It reflects the plateau in the myocardial action potential.

• It indicates the heart's natural pacemaking activity.

• It represents atrial repolarization.

What does the T wave on an ECG indicate?

• The delay of electrical impulses at the AV node.

• Ventricular depolarization.

• Atrial depolarization.

• Ventricular repolarization.