Graded Potential

Graded Potential

A small change (deviation) from the resting membrane potential that makes the membrane either more polarized or less polarized.

Graded Potential: Hyperpolarizing

A graded potential that makes the inside of the membrane more negative (more polarized) than the resting membrane potential.

Graded Potential: Depolarizing

A graded potential that makes the inside of the membrane less negative (less polarized) than the resting membrane potential.

Graded Potential: Causes

A stimulus causes mechanically gated or ligand-gated ion channels to open or close, producing a graded potential.

Graded Potential: Meaning

Graded means the size (amplitude) of the electrical signal varies depending on the strength of the stimulus

Graded Potential: Stimulus Strength

Depends on how many ligand-gated or mechanically gated channels have opened (or closed) and how long each remains open.

Graded Potential: Ion Movement

Opening or closing ion channels changes the movement of specific ions across the membrane, producing a localized electrical current.

Graded Potential: Localized Current

The electrical current produced by a graded potential spreads only a short distance along the plasma membrane from the stimulus source in either direction.

Graded Potential: Decremental Conduction

The gradual decrease in strength of a graded potential as it spreads away from its point of origin due to electrical charges being gradually lost

Graded Potential: Summation

Summation is the process in which multiple graded potentials add together, making the overall graded potential stronger or longer-lasting.

Summation: Depolarizing Potentials

When two depolarizing graded potentials summate, they produce a larger depolarizing graded potential.

Summation: Hyperpolarizing Potentials

When two hyperpolarizing graded potentials summate, they produce a larger hyperpolarizing graded potential.

Summation: Opposite Potentials

When equal but opposite depolarizing and hyperpolarizing graded potentials summate, they cancel each other out and the overall graded potential disappears.