Electrochemicla Gradient
Particular ions are distributed unequally across the cell membrane.
Concentrations of Na+ and Cl− are greater on the outside of the cell, while concentrations of K+ and organic anions, such as charged amino acids and proteins, are greater on the inside of the cell .
The organic ions are incapable of passing across the cell membrane.
This arrangement leads to an electrochemical gradient called the resting potential.