1. Cell Transport

2. Cell Transport = movement of molecules into and out of the cell

3. Two Main Types of Cell Transport
Passive Transport
2. Active Transport

4. Passive Transport
Passive transport – movement of particles across a cell membrane that requires NO energy

5. 3 types of passive transport: 1
3 types of passive transport: 1. diffusion – movement of particles from a high concentration to a low concentration (“down a concentration gradient”)

6. Diffusion

7. Things that increase rate of diffusion (speeds it up): ↑ stirring ↑ temperature ↑ surface area ↑ pressure ↑ concentration Eventually, all particles become evenly distributed (dynamic equilibrium).

8. Facilitated diffusion – diffusion with the
Facilitated diffusion – diffusion with the help of transport proteins that are embedded in the cell membrane
- some molecules are too big or polar (hydrophilic) to diffuse on their own

9. Osmosis – diffusion of water across a selectively permeable membrane
- water will move from a high concentration of water to a low concentration of water
- water always tries to reach an equal concentration on both sides of the membrane

10. Examples  … cell will SHRINK.
If concentration of water is greater inside the cell … 
… cell will SHRINK.

11. Examples  … cell will ENLARGE.
If concentration of water is greater outside the cell … 
… cell will ENLARGE.

12. Examples … cell will STAY THE SAME.
If concentration of water is equal on both sides …
… cell will STAY THE SAME.

13. Examples

14. Examples

15. Examples

16. Active Transport
Active transport – movement of particles across a membrane from a low concentration to a high concentration
(“against a concentration gradient”)

17. Active Transport
- Requires ENERGY!!

18. Types of Active Transport
Cell membrane pump
- carrier protein “pumps” molecules against a gradient

19. Endocytosis – cell surrounds and takes up material such as food

20. 3. Exocytosis – cell expels material such as wastes