Pacemaker cells in the SA node
A)have a well-defined resting potential.
B)can spontaneously depolarize.
C)also contract with the rest of the cells in the heart wall.
D)are special neurons that convey signals from the brain to the heart.
E)All of the answers are correct.

Question

Quizplus · Accepted Answer

Pacemaker cells in the SA node do not have a well-defined resting potential and can spontaneously depolarize, initiating the heartbeat. They are not neurons and do not contract with the rest of the cells in the heart wall. Therefore, only choice B is correct.

Pacemaker Cells in the SA Node