| A | B |
|---|
| active transport | the movement of a substance across a cell membrane against a |
| carrier protein | a protein that transports specific substances across a membrane |
| concentration gradient | the difference in concentration of a substance across |
| contractile vacuole | an organelle in protists that expels water (97) |
| cytolysis | the bursting of a cell |
| diffusion | the process by which molecules move from an area of greater |
| endocytosis | the process by which a cell takes in materials by forming a vesicle |
| equilibrium | a state that exists when the concentration of a substance is the |
| exocytosis | a process in which a vesicle inside a cell fuses with the membrane |
| facilitated diffusion | a process in which substances move down their gradient more quickly with help of carrier proteins |
| hypertonic | solution whose solute concentration is higher than that of the cell |
| hypotonic | a solution whose solute concentration is lower than that of the cell |
| ion channel | a membrane protein that provides a passageway across the cell membrane for charged atoms |
| isotonic | solution whose solute concentration equals that inside a cell |
| osmosis | the diffusion of water across a selectively permeable membrane (96) |
| passive transport | the movement of substances across a cell membrane without added energy |
| phagocyte | a cell that engages in phagocytosis (104) |
| phagocytosis | a type of endocytosis in which a cell engulfs large particles or cells |
| pinocytosis | a type of endocytosis in which a cell engulfs solutes or liquids |
| plasmolysis | the shrinking or wilting of a cell in a hypertonic |
| sodium-potassium pump | a carrier protein that actively transports K+ ions in and Na+ out of cell |
| turgor pressure | water pressure within a plant cell (98) |
| vesicle | a membrane-bound sac in a eukaryotic cell that contains materials |
