What would happen to the membrane potential if sodium ions were allowed to flow down their concentration gradient?
(a) the interior of the cell will become less negative
(b) the interior of the cell becomes less positive
(c) the exterior of the cell becomes less negative
(d) the exterior of the cell becomes more positive

a) The interior of the cell will become less negative.

Explanation:

The Sodium-Potassium pump pumps 3 sodium ions to the extracellular up their concentration gradient resulting in a more negative interior. When the sodium is allowed to move down their concentration gradient the interior would be less negative.

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