What causes the rapid depolarization phase of a contractile cell action potential?
A) sodium movement into the cell
B) calcium movement into the cell
C) potassium movement into the cell
D) calcium movement out of the cell
E) sodium movement out of the cell

Question

Quizplus · Accepted Answer

The rapid depolarization phase of a contractile cell action potential is primarily caused by the movement of sodium ions into the cell, which increases the positive charge inside the cell and leads to depolarization.

What Causes the Rapid Depolarization Phase of a Contractile Cell