At the beginning of an action potential,sodium moves
A) slowly into the cell,because electrical force is offset by diffusion.
B) rapidly into the cell,because both electrical force and diffusion will move sodium in the same direction.
C) slowly out of the cell,because as a positive ion,sodium remains attracted to the relatively negative intracellular environment.
D) rapidly out of the cell,because the sodium-potassium pumps are very active.

Question

Quizplus · Accepted Answer

At the beginning of an action potential, the membrane potential becomes more positive, which opens voltage-gated sodium channels. Due to both the electrical force (positive inside and negative outside) and the concentration gradient (higher concentration outside), sodium ions move rapidly into the cell, leading to depolarization.

At the Beginning of an Action Potential,sodium Moves