Question

A resting neuron is (i)_____ and has a membrane potential of (ii)______.

• A. (i) Polarized (ii) -55mV
• B. (i) Electrochemically neutral (ii) 0 mV
• C. (i) Hyperpolarized (ii) -100mV
• D. (i) Polarized (ii) -70mV

Answer 1

The correct option is D

(i) Polarized (ii) -70mV

A resting neuron is polarized at a membrane potential of -70mV, with greater negative charge inside. When there is a change in the membrane potential with the inside becoming more positive, the neuron is depolarized. If the membrane potential drops to below the normal resting state of -70mV, the neuron is hyperpolarized. Cells do not stay in a state of electrochemical neutrality because there is an uneven distribution of ions across a cell membrane.