- Active transport: The movement of materials through a cell membrane using cellular energy
- diffusion: The main methos by which small molecules move across the cell membrane also is the process by which molecules move from an area of lower concentration to higher concentration
- osmosis: is the diffusion of water molecules through a selectively permesble membrane
- Passive Transport: the movement of materials through a cell membrane without using cellular energy
- selectively permeable: some substances can pass throught the membrane while others can't