The polarization of a nerve fiber refers to having the
A) sodium and potassium ions inside the cell.
B) sodium ions inside the cell and potassium outside the cell.
C) potassium ions inside the cell and sodium outside the cell.
D) chloride ions inside the cell.
E) hillock and knob at opposite ends.

Question

Quizplus · Accepted Answer

Polarization of a nerve fiber refers to the difference in charge between the inside and outside of the cell. In resting state of a neuron, potassium ions inside the cell are more concentrated than the sodium ions outside the cell. At this time, there is an excess of negative charges inside the cell which leads to a potential that is negative compared to the outside. This difference in potential, which is typically around -70mV, is called the resting membrane potential. This configuration of having more potassium ions inside the cell than outside contributes to the polarization of the nerve fiber. Therefore, the correct option is C, that is, potassium ions inside the cell and sodium outside the cell.

The Polarization of a Nerve Fiber Refers to Having the