Electrical System of the Heart

Front

What does the PR interval on an electrocardiogram (ECG) represent?

Back

The time taken for the electrical impulse to travel from the SA node to the AV node.

Front

What does the QRS complex on an ECG represent?

Back

Ventricular depolarization.

Front

What occurs during complete heart block?

Back

The AV node fails to transmit the electrical impulse.

Front

What term describes the coordinated contraction of the atria followed by the ventricles?

Back

Cardiac cycle.

Front

What is the normal heart rate range for adults?

Back

60-100 beats per minute.

Front

What is the function of the SA node in the heart?

Back

It acts as the natural pacemaker, initiating the electrical impulse that triggers heartbeats.

Front

What is the role of the AV node in the electrical conduction system of the heart?

Back

It serves as a gatekeeper, slowing down the electrical impulse before it enters the ventricles.

Front

What is diastole in the cardiac cycle?

Back

The phase of the heartbeat when the heart muscle relaxes and the chambers fill with blood.

Front

What is systole in the cardiac cycle?

Back

The phase of the heartbeat when the heart muscle contracts and pumps blood out of the chambers.

Front

What is the significance of the T wave on an ECG?

Back

It represents ventricular repolarization.