Final answer:
The number of ions forming layers of charge on the membrane is smaller than the total number of ions, due to the limiting effect of the Coulomb force. These ions create a voltage across the membrane which is fundamental for electrical signal transmission in cells.
Step-by-step explanation:
The total number of ions in a solution is much larger than the number of ions lined up against the membrane. The Coulomb force restricts the build-up of these ions to create just two layers of charge directly on the cellular membrane. The diffusion of ions like K+ (potassium) and Cl- (chloride) across the membrane is balanced by this Coulomb force, preventing unlimited movement and maintaining electrical neutrality overall, while also establishing a voltage across the membrane.
Large anions, that are part of the inner membrane, contribute to the negative charge inside the cell. The resting state of the membrane presents a predictable distribution of ions, with a higher concentration of Na+ outside than inside, and vice versa for K+ ions. This structure contributes to the potential differences across the membbrane, vital for the transmission of electrical signals.