Why does depolarization of a cardiac muscle cell occur?
A) There is a decrease in the permeability of the cell membrane to ions.
B) A rapid movement of ions across the cell membrane occurs.
C) A blockade by calcium ions takes place.
D) There is a stimuli instigated during the refractory period.

Question

Quizplus · Accepted Answer

Depolarization occurs due to the rapid influx of sodium ions into the cell, changing the electrical charge across the cell membrane.

Why Does Depolarization of a Cardiac Muscle Cell Occur