Which of the following does not characterize pacemaker cells?
A) They are modified cardiac muscle cells.
B) Their action potentials rise rapidly.
C) They can initiate action potentials without stimulation from the nervous system.
D) They fire action potentials and stimulate neighboring cells to contract.
E) Their action potentials are broader than those of neurons.

Question

Quizplus · Accepted Answer

Pacemaker cells have action potentials that rise slowly due to the gradual influx of calcium ions, not rapidly. This slow depolarization is crucial for the heart's rhythmic contractions, distinguishing them from the rapid action potential rise seen in other types of cells.

Which of the Following Does Not Characterize Pacemaker Cells