| 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 a membrane |
| diffusion | the process by which molecules move from an area of greater concentration to an area of lesser concentration |
| endocytosis | the process by which a cell surrounds and engulfs particles and takes them into the cell |
| equilibrium | a state that exists when the concentration of a substance is the same throughout |
| exocytosis | a process in which a vesicle inside a cell fuses with the cell and expels material from the cell |
| facilitated diffusion | a process in which substances move down their protein channel for transport into or out of the cell |
| hypertonic | describing a solution whose solute concentration is higher than that inside the cell |
| hypotonic | describing a solution whose solute concentration is lower than that inside the cell |
| isotonic | describing a solution whose solute concentration equals that inside a |
| osmosis | the diffusion of water across a selectively permeable membrane |
| passive transport | the movement of substances across a cell membrane without energy expenditure |
| phagocytosis | a type of endocytosis in which a cell engulfs large particles |
| pinocytosis | a type of endocytosis in which a cell engulfs liquid |
| vesicle | a membrane-bound sac in a eukaryotic cell that contains materials |
