| A | B |
|---|
| permeable | anything can pass through |
| impermeable | nothing can pass through |
| selectively permeable | some things can pass through and some things cannot pass through |
| passive transport | requires no energy |
| active transport | requires energy |
| diffusion | molecules move from an area of high concentration to an area of low concentration until they are equal |
| osmosis | water moves from high to low concentration until equal |
| engulfing | cell membrane surrounds a particle and takes it in |
| diffusion and osmosis | two methods of passive transport |
| pick up and engulfing | two methods of active transport |
