Cellular proteins are ampholytes, i.e., those electrolytes that have, at the same time, acidic and basic functions. In sum, when an ampholyte is placed in a beaker with electrodes, it moves to the negative pole in an acid medium, and inversely, when the net situation is electrically neutral, it will not behave either as an anion or a cation, remaining neutral. This electrical neutrality does not usually conform to the postulates of chemistry, but each ampholyte has a specific value and the constancy of this characteristic is its isoelectric point. The activity of the cell depends on the electrocapillary effects introduced by the molecular condenser which is the result of the orientation of the proteins in the membrane. The rate of diffusion will depend on the size of the molecules and the diffusable substance, and on its molecular weight and electrical charge.
Electrolytes behave as normal molecules.
It should be noted, too, that erythrocytes are very sensitive osmometers. So that normal cell functions can be carried out, it Is necessary that the osmotic pressure be consistently constant both within the cell and in the surrounding environment, since the protoplasm is a complex system in which the ratio between the water and the dissolved substances can only vary within a very limited range. The small variations in the quantity of protoplasmic water are immediately revealed in abnormality of cell functioning, and this becomes more important as the function of the affected cells becomes more delicate. The rate of the intracellular reaction is proportional to the concentration of the ions. There is a permanent fixed state of fluidity that permits normal functioning.