If you experimentally increase the concentration of Na⁺ outside a cell while maintaining other ion concentrations as they were, what would happen to the cell's membrane potential?
A) The membrane potential would become more negative.
B) The membrane potential would become more positive.
C) The membrane potential would be unaffected.
D) The answer depends on the thermodynamic potential.

Question

Quizplus · Accepted Answer

Increasing the concentration of Na⁺ outside the cell will result in a decrease in the concentration gradient of Na⁺ across the membrane. Since Na⁺ is positively charged, a decrease in its concentration gradient would result in a more positive membrane potential. Therefore, the membrane potential would become more positive.

If You Experimentally Increase the Concentration of Na⁺ Outside a Cell