Define Solute-Solvent Interaction
A solution, as you may already know, is a mixture of solute (present in small amount) and solvent (present in large amount). The interaction between solute-solvent inside the cell and outside the cell is governed by many physical factors like concentration gradient, electrical gradient, osmotic pressure difference and the characteristics of the membrane.
Some molecules come out of the membrane through it gates and for others selective transport through these gates is permissible. But for all living excitable cells, there is a potential difference during the resting state which is always negative towards inside the cell. When the cell becomes active, this potential difference is reversed and this is called action potential. So this interaction of solutes-solvent outside and inside maintain this important cell activity i.e., excitability. The main factors given below are responsible for this activity.