If the cells of the SA node failed to function,how would the heart rate be affected?
A)The heart would beat faster because the AV node would be the pacemaker.
B)The heart would beat slower because the AV node would be the pacemaker.
C)The heart would stop beating because the SA node was not acting as the pacemaker.
D)The heart would go into an arrhythmia because the Purkinje fibers would try to be the pacemaker.
E)The heart would beat faster because the inherent rate of myocardial depolarization is faster than the SA node pacemaker.

Question

Quizplus · Accepted Answer

The SA node is considered the natural pacemaker of the heart because it initiates the electrical impulses that regulate the heartbeat. If the cells of the SA node fail to function, the AV node will take over as the pacemaker but at a slower rate, resulting in a slower heart rate. Therefore, the heart would beat slower because the AV node would be the pacemaker.

If the Cells of the SA Node Failed to Function,how