1. II. Membrane Transport Two types: Passive & Active
A. Passive Transport - does not require energy
1. Diffusion - process where molecules move from an area where they are more concentrated to an area where they are less concentrated

2. II. Membrane Transport

3. II. Membrane Transport
2. Osmosis - the diffusion (high to low concentration) of water through a selectively permeable membrane

4. II. Membrane Transport Type of Solution Plant Cell Animal Cell
__________________ - net flow of water is into a cell
__________________ – water moves in and out of the cell at equal rates
__________________ - net flow of water is out of the cell

5. II. Membrane Transport
3. Facilitated Diffusion – When a carrier molecule transports solute molecules across the membrane
Speed up diffusion
Carry large molecules that can’t diffuse quickly across cell membrane

6. II. Membrane Transport

7. Review of types of Passive Transport

8. II. Membrane Transport
B. Active Transport – the movement of any substance across a cell membrane with the use of chemical energy
Requires energy & a carrier protein
Against the concentration gradient – moving low to high (paddling up a river)

9. II. Membrane Transport
Transport proteins – Special transport molecules in the cell membrane move molecules across the cell membrane
Moves particles from low concentration to high concentration – pumps

10. II. Membrane Transport
Endocytosis – bringing large particles into the cell
Pinocytosis – Movement of solutes or fluids into the cell. “Cell drinking”
Phagocytosis – Movement of large food particle or whole microorganisms into the cell. “Cell eating”

11. II. Membrane Transport

12. II. Membrane Transport
Exocytosis – removal or large particles from a cell