| A | B |
|---|
| diffusion | movement of molecules from high to low concentration |
| passive transport | movement of molecules across a membrane without need for energy |
| concentration gradient | difference in concentration across a distaance |
| equilibrium | when the concentration is the same throughout a distance |
| osmosis | diffusion of water from high to low concentration |
| hypotonic | when solution outside the cell is lower in solute than inside |
| hypertonic | when concentration outside the cell is higher in solute than inside |
| isotonic | when the concentration of solute is the same both inside and outsde a cell |
| contractile vacuole | organelles in single celled organisms that pump water out |
| turgor pressure | the pressure of water molecules against the cell wall |
| plasmolysis | when the cell shrinks froms the cell wall: due to hypertonic solution |
| cytolysis | when cells swell and burst: due to hypotonic solution |
| facilitated diffusion | passive transport (diffusion), but through carrier proteins |
| carrier protein | inside the membrane, they move molecules from high to low concentration and do not require energy |
| ion channel | always open and located in the membrane, they help ions move from high to low concentration and do not require energy |
| active transport | movement of materials against the concentration gradient; requires ATP |
| sodium potassium pump | example of active transport with a carrier protein: 3 Na+ out and 2 K+ in |
| endocytosis | when cells ingest large particles and bring them in the cell |
| vesicle | a membrane pouch that transports materials in and out of the cell |
| pinocytosis | when cells take in fluids into the cell |
| phagocytosis | when cells take in large materials into the cell |
| phagocyte | cells that use phagocytosis to ingest bacteria and viruses |
| exocytosis | a process that releases substanes in vesicles outside the cell |
