Depolarization of a cardiac muscle cell occurs as the result of:
A) a decrease in the permeability of the cell membrane to ions.
B) the rapid movement of ions across the cell membrane.
C) a blockade by calcium ions.
D) stimuli instigated during the refractory period.

Question

Quizplus · Accepted Answer

Depolarization of a cardiac muscle cell is primarily due to the rapid influx of sodium ions into the cell, which changes the electrical charge across the cell membrane.

Depolarization of a Cardiac Muscle Cell Occurs as the Result