The resting membrane potential in nerve and skeletal muscle is determined primarily by
A) extracellular sodium ion concentration.
B) the ratio of intracellular to extracellular potassium ion.
C) activation of voltage-gated sodium channels.
D) activity of energy-dependent membrane ion pumps.

Question

Quizplus · Accepted Answer

At equilibrium,the electrical gradient pulling K⁺ into the cell and the chemical gradient pulling it out are balanced.This equilibrium point leaves a few extra negatively charged ions inside the cell with no positive ion to neutralize them.The resting membrane potential in nerve and skeletal muscle is not determined by the extracellular sodium concentration.The membrane potential changes in response to potassium changes.Ion channels open and close in response to fluctuations in membrane voltage,but the resting membrane potential is not determined by the activity of membrane ion pumps.

The Resting Membrane Potential in Nerve and Skeletal Muscle Is