Membrane Potential

Membrane Potential

The difference of electrical charges across a cell membrane.

Transmembrane Potential

Most cells have a negative transmembrane potential, indicating more negative charges inside the cell.

Ion Movement Rule 1

Ions move from areas of higher concentration to lower concentration.

Ion Movement Rule 2

Ions move away from like charges and toward opposite charges.

Permeability

The ability of a membrane to allow specific ions to pass through, achieved by ion channels.

Ion Channels

Passageways in the cell membrane that open or close to allow specific ions to pass.

Equilibrium Potential for Sodium

The voltage required to maintain the concentration gradient of sodium across the membrane.

Resting Membrane Potential

The typical resting membrane potential of a neuron is about -70 mV.

Equilibrium Condition for Chloride

Chloride requires a negative environment inside the cell to maintain its equilibrium.

Active Transport

Process by which sodium and potassium are kept out of equilibrium in resting neurons.

Electrostatic Force

The force driving charged particles toward opposite charges and away from like charges.

Diffusion Force

The force that drives particles from areas of higher concentration to lower concentration.

Concentration Gradient

A difference in the concentration of a substance across a membrane.

Equilibrium

The state reached when the net movement of sodium ions is zero due to opposing forces.

Chloride Equilibrium Potential

Chloride has an equilibrium potential close to the resting membrane potential due to its charge.