1. Let’s Move…Cell Transport

2. Millions of Molecules Moving
What is the temperature of the water?
How can you tell?

3. Diffusion of Molecules
What is the deal with the red dots…can you relate them to what we did in class?

4. Movement Across the Cell Membrane
One of the most important functions of the cell membrane is to control the movement of dissolved molecules from the liquid on one side of the membrane to the liquid on the other side.

5. Concentration Gradient
Distribution of particles across space from high to low.
The concentration gradient is a difference in concentration between two areas.

6. Sliding Down
Particles tend to move from an area where they are more concentrated to an area where they are more concentrated to an are where they are less concentrated.

7. Passive Transport: Simple Diffusion
The movement of particles across a cell membrane from areas of high concentration to areas of low concentration…requiring NO ENERGY.
This process is also called diffusion.

8. Passive Transport: Facilitated Diffusion
Facilitate: to aid or assist
Diffusion: movement from H to L
Movement from high to low with help.

9. Passive Transport: Osmosis
Water passes easily across most membranes
They diffusion of water across a semi- permeable membrane is called OSMOSIS.
Semipermeable means that some substances can pass through, while others cannot.

10. Passive Transport: Osmosis

11. Solutes and Solvents
Dissolve: to make a solution, as if by mixing with a liquid
Example…dissolving salt in water
Solute: things that get dissolved.
Salt
Solvent: things that do the dissolving.
Water

13. Tonicity Tonic: amount of dissolved substances Hyper: high,rush
Hypo: low,grow
Iso: Equal,stay

14. Hypertonic Hyper=high tonic=amount of dissolved substances
Describes a solution with a higher solute concentration compared with another solution

15. Hypotonic Hypo=low tonic=amount of dissolved substances
Describes a solution with a lower solute concentration compared with another solution

16. Isotonic Iso=equal tonic=amount of dissolved substances
Describes a solution with a equal solute concentration compared with another solution

19. Tonicity Problems…gotta solve ‘em

20. Practice Problems…where does the water go?
100% H2O
20% H2O

21. Practice Problems
50% H2O
100% H2O
50% H2O
80% H2O

22. Practice Problems
70% salt
25% H2O
30% salt
75% H2O

23. Practice Problems
50% salt
1% salt
50% salt
99% salt