The normal pacemaker of the heart is the _____ node, which is found in the _____ atrium, and has an intrinsic firing rate of _____ beats/min.
A) sinoatrial; left; 40 to 60
B) sinoatrial; right; 60 to 100
C) atrioventricular; left; 20 to 40
D) atrioventricular; right; 100 to 180

Question

Quizplus · Accepted Answer

The sinoatrial (SA) node is normally the primary pacemaker of the heart because it has the fastest firing rate of all of the heart's normal pacemaker sites (60 to 100 beats/min). The SA node is located in the upper posterior part of the right atrium where the superior vena cava and the right atrium meet.

The Normal Pacemaker of the Heart Is the _____ Node