| 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 biological |
| concentration gradient | the difference in concentration of a substance across |
| diffusion | the process by which molecules move from an area of greater |
| hypertonic | describing a solution whose solute concentration is higher than that |
| hypotonic | describing a solution whose solute concentration is lower than that |
| isotonic | describing a solution whose solute concentration equals that inside a |
| osmosis | the diffusion of water across a selectively permeable membrane (96) |
| passive transport | the movement of substances across a cell membrane without |
| homeostasis | process of maintaining stable conditions |
