Cell Transport

osmosis

the movement of water molecules across a selectively permeable membrane from an area of lower concentration to an area of higher concentration

diffusion

the process by which molecules spread from areas of high concentration to areas of low concentration until equilibrium is reached

active transport

the movement of molecules across a cell membrane WITH the use of energy, typically against their concentration gradient

passive transport

the movement of substances across a cell membrane WITHOUT the use of energy, moving along the concentration gradient

cell transport

the processes that regulate the movement of substances into and out of cells, including diffusion, active transport, and passive transport

concentration gradient

the difference in the concentration of a substance from one location to another

permeable

allows ALL materials to pass through the cell membrane freely

impermeable

does not allow materials to pass through

semi-permeable

allows certain materials to pass while restricting others. Also know as “selectively permeable”

cell membrane

the semi-permeable structure that surrounds and protects the cell, regulating the movement of substances in and out

solute

a substance that gets dissolved in a solution, typically in lesser amount compared to the solvent

solvent

a substance that dissolves a solute, forming a solution

concentration (of a solution)

the measured amounts of both solvents and solutes in a solution