Biology Study Set: Diffusion & Osmosis Terms & Definitions

Diffusion

Movement of particles or molecules from an area of high concentration to an area of low concentration

Osmosis

Diffusion of water across a selectively permeable membrane

Selectively pemeable membrane

A membrane that allows certain materials to pass through, but not others

Dynamic equilibrium

condition of continuous, random movement of particles but no overall change in concentration of materials

Solute

substance that is dissolved in a solution

Solvent

the liquid that contains the dissolved solute in a solution.

Cell Membrane

regulates and controls what enters or leaves the cell

Facilitated Diffusion

this form of diffusion is regulated by protein channels in the membrane and requires no energy input from the cell

Active Transport

movement of molecules or ion into or out of the cell against its concentration gradient (from low to high) and requires an input of energy.

Endocytosis

movement of substances into the cell by creating a new vacuole at the cell membrane. requires energy.

Exocytosis

movement of substances out of a cell by merging a vacuole with the cell membrane. requires energy.

Transport Protein

Proteins within the cell membrane that function to move substances into or out of the cell.