Question

When sodium channels open during an action potential, the opening is caused by

A. binding of sodium ions.

B. binding of potassium ions.

C. presence of calcium.

D. presence of positive charge.

Answer 1

Sodium channels open during an action potential due to the binding of sodium ions, which leads to depolarization of the membrane.

Step-by-step explanation:

The opening of sodium channels during an action potential is caused by the binding of sodium ions. When an action potential occurs, voltage-gated sodium channels in the cell membrane of nerve cells open in response to the entry of sodium ions. This influx of sodium ions into the cell depolarizes the membrane and triggers the generation of an action potential.