Chapter 1.2, Problem 2EIQ

Summary Introduction

Introduction:

The electrical gradient or polarization is the difference in the electric charge inside and outside the cell. Similarly, concentration gradient is the concentration of an ion inside and outside the cell. The electrical potential of a nerve cell is slightly negative (-70mV) inside the cell than the outside, due to the presence of negatively charged proteins inside the cell. All ions and molecules cannot freely pass through the membrane due to the selective permeability of the membrane. When the neuron is at rest, sodium concentration is more on the outside of the cell, due to sodium-potassium pump, creating a concentration gradient, and electrical gradient, which tend to drive the sodium ions into the cell.