Which of the following is TRUE regarding the resting potential of a neuron?
A) In mammals it is about -20 millivolts.
B) During its resting state, all ionized particles can move freely into and out of the neuron.
C) The potential is maintained by high concentrations of magnesium outside the neuron.
D) The predominant charge inside a neuron at rest is negative.

Question

Quizplus · Accepted Answer

The resting potential of a neuron is the membrane potential when the neuron is not sending a signal. The predominant charge inside a neuron at rest is negative due to the higher concentration of negatively charged ions, such as proteins and organic anions, compared to positively charged ions, such as sodium and potassium. The resting potential is typically around -70 millivolts in mammals. Option A is incorrect because the resting potential is around -70 millivolts, not -20 millivolts. Option B is incorrect because during the resting state, ionized particles cannot move freely across the membrane due to the selective permeability of the membrane. Option C is incorrect because magnesium is not involved in maintaining resting potential; instead, it is the concentration gradients of potassium and sodium ions that contribute to resting potential.

Which of the Following Is TRUE Regarding the Resting Potential