1. TEST: FRIDAY 11/11 CELL TRANSPORT

2. CELL MEMBRANE PERMEABILITY Semi- permeable— allows small substances to pass through freely Larger substances must pass through channels Lipid bilayer

3. FLUID MOSAIC MODEL

4. DIFFUSION Molecules always move from HIGH to LOW concentrations Occurs due to a concentration gradient Effective only across a small distance Diffusion/Osmosis Animations Click the pic to watch the video

6. M & M DEMO 1.Take a petri dish and fill it with water 2.Place 4 different color M&Ms into the water 3.Observe what happens What is this process called?? DIFFUSION!! Will all the colors evenly distribute in time? YES!!

7. MEMBRANE TRANSPORT Passive transport— type of simple diffusion Molecules move from HIGH to LOW concentration Osmosis—diffusion of water Facilitated diffusion occurs through protein channels

8. SOLUTE CONCENTRATIONS Isotonic: equal amounts of solutes Hypotonic: solution has lower solute concentration (H 2 0 IN—cell bursts) Hypertonic: solution has higher concentration of solutes (H 2 0 OUT—cell shrinks) Diffusion/Osmosis Animations

9. OSMOSIS Diffusion of water Occurs easily through bi-lipid layer Click pic to watch the video

11. FACILITATED DIFFUSION Molecules pass through or bind to a protein channel to cross a membrane

12. FACILITATE DIFFUSION THROUGH CARRIER PROTEINS When a substance being transported binds to protein Moves from HIGH to LOW Click above to watch a video showing facilitated diffusion