Diffusion

the process of moving molecules from areas of high concentration to low concentration until equilibrium is reached.

Osmosis

diffusion of water from areas of high concentration of water molecules to low concentration of water molecules. (Remember that the amount of solute present can affect this. )

facilitated diffusion

Diffusion of molecules that uses a channel protein to move the molecules into or out of the cell.

active transport

movement of molecules from areas of low concentration to high concentration (against the concentration gradient)

Requires ATP

Requires a special transport protein

Endocytosis

a type of active transport that brings large molecules into the cell. The cell membrane envelops the particle and is pushed into the cell.

Phagocytosis

cell eating (taking in large solid particles by endocytosis)

Pinocytosis

cell drinking (taking in large droplets of liquid into the cell by endocytosis)

exocytosis

removing large particles from the cell. The particle is enclosed in a vesicle and the phospholipids of the vesicle fuse to the cell membrane and push the contents out of the cell.

passive transport

transport of molecules that moves with the concentration gradient

does not require energy

includes diffusion, osmosis, facilitated diffusion

ATP

adenosine tri-phosphate

Energy used for chemical reactions

hypertonic environment

solution that is highly concentration

cells placed in this solution will shrivel

hypotonic environment

solution that has little to no solute concentration

cells placed in this solution will swell and burst

isotonic

environment where there water leaving and entering the cell is at equillibrium