Opening all of the sodium channels of a neuron at rest should move its membrane potential to ________.
A) −90 mV
B) −70 mV
C) 0 mV
D) +10 mV
E) +40 mV

Question

Quizplus · Accepted Answer

Opening all the sodium channels of a neuron at rest would result in a massive influx of positively charged sodium ions into the cell, driving the membrane potential to become more positive. Given that the resting membrane potential of a neuron is typically around -70 mV, opening all the sodium channels would bring the potential closer to the sodium equilibrium potential, which is typically around +40 mV. Therefore, the membrane potential would move to +40 mV if all the sodium channels were opened.

Opening All of the Sodium Channels of a Neuron at Rest