Concentration Gradient

Definition

A concentration gradient occurs when there is a difference in concentration of a particular substance between two regions. Substances will naturally move from areas of high concentration to areas of low concentration until equilibrium is reached.

Related terms

Diffusion:

This refers to how particles spread out from an area of high concentration to an area of low concentration.

Osmosis:

A special type of diffusion involving water molecules moving across a semi-permeable membrane from an area with more water (low solute concentration) towards less water (high solute concentration).

Equilibrium: The state where concentrations are equal throughout a space; no net movement occurs once this state has been reached.