1. Cell MembranesOsmosis and Diffusion

2. PREFIX – SUFFIX ADDITIONS Hypo – under, beneath, lacking Hyper – over, above, excess Iso – equal Tonic – stretching, tone

3. Functions of Membranes 1. Protect cell 2. Control incoming and outgoing substances Maintain ion concentrations of various substances FLASH CARD ALERT!!! 4. SELECTIVELY PERMEABLE - allows some molecules in, others are kept out

4. Phospholipid Bilayer

5. Fluid Mosaic Model

6. Solutions Solutions are made of solute and a solvent FLASH CARD ALERT!!!! SOLVENT - the liquid into which the solute is poured and dissolved. We will use water as our solvent in Lab #4 SOLUTE - substance that is dissolved or put into the solvent. Salt and sucrose are solutes.

7. Methods of Transport Across Membranes 1. Diffusion 2. Osmosis 3. Facilitated Diffusion 4. Active Transport

8. FLASH CARD ALERT!!! 1. DIFFUSION -passive transport of molecules - no energy expended 2. OSMOSIS- Passive transport of WATER across membrane 3. FACILITATED DIFFUSION- Use of carrier proteins to carry polar molecules or ions across membrane 4. ACTIVE TRANSPORT requires energy to transport molecules AGAINST A CONCENTRATION GRADIENT. energy is in the form of ATP

9. Where does that ATP come from?

10. Diffusion Movement of molecules from an area of high concentration to an area of low concentration. DIFFUSION = MOVEMENT OF MOLECULES OSMOSIS = MOVEMENT OF WATER.

11. Diffusion

12. Facilitated Diffusion

13. Passive – Does not require energy Uses carrier proteins Molecules combine with carrier proteins. These molecules speed up the passage over the membrane. Glucose

14. Osmosis

15. Tonicity is a relative term FLASH CARD ALERT!!! Hypotonic Solution - One solution has a lower concentration of solute than another. Hypertonic Solution - one solution has a higher concentration of solute than another. Isotonic Solution - both solutions have same concentrations of solute.

16. Plant and Animal Cells put into various solutions

17. Carrier Proteins CARRIER PROTEINS – bind to a specific type of diffusing molecule. They have a highly specific hydrophilic region to which the solute molecule binds. This binding cause the protein to undergo a change in shape that moves the solute across the bilayer and release it on the other side

18. Active Transport Active transport is the transport of molecules by carrier proteins AGAINST a concentration gradient. REQUIRES ENERGY IN THE FORM OF ATP

19. Types of Transport

20. http://www.youtube.com/watch?v=sdiJtDRJQEc&safety_mode=true&persist_safety_mode=1&safe=active