When a neuron's membrane is at rest, the concentration gradient tends to move sodium ____ the cell and the electrical gradient tends to move it ____ the cell.
A) into; into
B) into; out of
C) out of; into
D) out of; out of

Question

Quizplus · Accepted Answer

The concentration gradient moves sodium ions into the cell because there are more sodium ions outside the cell than inside. The electrical gradient also moves sodium ions into the cell because the inside of the cell is negatively charged relative to the outside, attracting the positively charged sodium ions.

When a Neuron's Membrane Is at Rest, the Concentration Gradient