What structure primarily controls the heartbeat in the human body?

Which of the following is not part of the cardiac conduction system?

Which of the following indicates ventricular depolarization in the heart's electrical conduction system?

A client is administered atropine to increase the heart rate. What is the action of atropine on the heart's electrical activity?

The pacemaker potential is also called which of the following?

What initiates the release of calcium from the sarcoplasmic reticulum in cardiac muscle cells?

Which of the following descriptions of cardiac pacemaker cells is incorrect?

Which of these statements about the heart is true?