Question

The interior of the neuron is at a potential of about _____ mV relative to the exterior.

(a) -70

(b) +70

(c) -170

(d) +170

This question was addressed to me during an interview.

Question is taken from Silver-Silver Chloride Electrodes in division Bioelectric Signal and Electrodes of Biomedical Instrumentation

Answer 1

Correct answer is (a) -70

Easiest explanation: The neurons, like the other cells of the body, are electrically polarized at rest. The interior of the neuron is at a potential of about -70 mV relative to the exterior. When a neuron is exposed to a stimulus above a certain threshold, a nerve impulse, seen as a change in membrane potential, is generated which spreads in the cell resulting in the depolarization of the cell.