After the Depolarization Phase of an Action Potential,the Resting Potential

Question

After the depolarization phase of an action potential,the resting potential is restored by
A)the opening of sodium activation gates.
B)the opening of voltage-gated potassium channels and the closing of sodium channels.
C)a decrease in the membrane's permeability to potassium and chloride ions.
D)a brief inhibition of the sodium-potassium pump.
E)the opening of more voltage-gated sodium channels.

Accepted Answer

After the depolarization phase of an action potential, the membrane potential becomes positive due to the influx of positively charged ions like sodium. To restore the resting potential, voltage-gated potassium channels open and potassium ions move out of the cell, while sodium channels close. This process of outward movement of potassium ions, which are more abundant inside the cell, leads to the hyperpolarization of the membrane potential, making it more negative than the resting potential. This allows the sodium-potassium pump to pump out the excess sodium ions and bring in the potassium ions to restore the resting potential.