1. Cell Transport
7.3

2. Passive Transport
No energy required
Materials move across membrane in order to maintain homeostasis

3. Types
(1) Diffusion
– Movement of molecules from High  Low concentration
- move H L until reach equilibrium ( = when concentration of particles on both sides of membrane is same)
- particles now move in/out at equal rate

4. (2) Facilitated diffusion
– molecules that cannot directly diffuse across membrane are helped through by protein channels in membrane
- occurs fast

5. (3) Osmosis – Diffusion of water through a membrane
Types of solutions:
* Hypertonic solution – solution has higher solute concentration than the cell
- water leaves cell
- cell shrinks

6. * Hypotonic solution – solution has lower solute concentration than cell
- water goes into cell

8. * Isotonic solution – solute concentration is same inside and outside cell
- water enters/exits at equal rate

10. Osmotic pressure = force exerted on cell based on movement of water in/out of cell
In hypotonic solutions, water enters cell; cell swells
- in animals, can burst
- in plants, wall prevents bursting