The membrane potential of a cell in non excited state is called Resting Membrane Potential (RMP). RMP of large nerve fiber is –90 mV. It allows a cell to function as a battery, providing power to operate a variety of “molecular devices” embedded in the membrane. In electrically excitable cells, it is used for transmitting signals between different parts of a cell. Membrane potential is contributed by the electrical force from mutual attraction between particles with opposite charges and repulsion between the particles with same charges. Diffusion also contributes to membrane potential by the tendency of particles to redistribute from regions of high concentration to low due to thermal energy. The diffusion potential across the membrane that exactly opposes the net diffusion of a particular ion through the membrane is called the Nernst potential for that ion. Factors responsible for generation of RMP are Na+K+ pump and leakage of K+. Membrane potential can be measured by patch clamp methods and voltage sensitive fluorescent dyes. Bioelectric properties can serve as markers for cell characterization, control cell mitotic activity and also cell cycle progression and differentiation.

Keywords: Resting Membrane Potential; Nernst Potential; Na+K+ Pump; Bioelectric Properties.