| Structure of the Lipid Bilayer | composition of nearly all cell membranes as a double-layered sheet; 2 layers of lipids gives membranes a flexible structure that forms a strong barrier between the cell & its surroundings |
| Diffusion | process by which molecules tend to move from an area where they are more concentrated to an area where they are less concentrated |
| Osmosis | diffusion of water through a selectively permeable membrane |
| Facilitated Diffusion | movement of specific molecules across cell membranes through protein channels |
| Isotonic | when the concentration of 2 solutions is the same |
| Hypertonic | when comparing2 solutions, the solution with the greater concentration of solutes |
| Hypotonic | when comparing 2 solutions, the solution with the lesser concentration of solutes |
| Active Transport | energy requiring process that moves material across a cell membrane against a concentration difference |
| Endocytosis | process by which a cell takes material into the cell by infolding of the cell membrane |
| Phagocytosis | process by which extensions of cytoplasm surround & engulf large particles & take them into the cell |
| Pinocytosis | process by which a cell takes in liquid from the surrounding environment |
| Exocytosis | process by which a cell releases large amounts of material |