Definition for Concentration gradient
From Biology Forums Dictionary
1) A gradual change in the concentration of solutes in a solution as a function of distance through a solution.
2) the gradual difference in the concentration of solutes in a solution between two regions. In biology, a gradient results from an unequal distribution of ions across the cell membrane. When this happens, solutes move along a concentration gradient. This kind of movement is called diffusion.
3) Is the difference in the concentration of a chemical between one side of the plasma membrane and the other.
