| A | B |
|---|
| active transport | the movement of a substance across a cell membrane against a concentration gradient |
| carrier protein | a protein that transports specific substances across a biological 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 (99) |
| diffusion | the process by which molecules move from an area of high concentration to an area of low concentration. |
| endocytosis | the process by which a cell surrounds and engulfs particles, liquids and even other cells. |
| equilibrium | a state that exists when the concentration of a substance is the same both inside and outside the cell. |
| exocytosis | a process in which a sac inside a cell fuses with the cell membrane and releases its contents. |
| facilitated diffusion | a process in which substances move down their |
| hypertonic | describing a solution whose solute concentration is higher than that which is inside the cell |
| hypotonic | describing a solution whose solute concentration is lower than that which is inside the cell |
| ion channel | a membrane protein that provides a passageway across the cell for ions |
| isotonic | Describing a 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 energy |
| phagocytosis | a type of endocytosis in which a cell engulfs large particles or |
| pinocytosis | a type of endocytosis in which a cell engulfs solutes or |
| plasmolysis | the shrinking or wilting of a walled cell in a hypertonic |
| sodium-potassium pump | a carrier protein that actively transports K+ ions |
| turgor pressure | water pressure within a plant cell (98) |
