Crossing the Membrane, Facilitated Diffusion and Active Transport

1. Crossing the Membrane,Facilitated Diffusion and Active Transport Day 3

2. Facilitated Diffusion • Facilitated Diffusion – Transport of substances from high concentration to low with aid of proteins • Remember, diffusion is ALWAYS high to low. • Molecules are ‘allowed’ to pass through membrane with help of Carrier Proteins • No energy needed

3. http://www.youtube.com/watch?v=s0p1ztrbXPY

4. Active Transport • Active Transport – Movement of substances across a cell membrane from an area of low to high concentration WITH the use of energy. • Against the Concentration Gradient • Low -> High concentration • Endocytosis - Exocytosis

5. Two Types: • Endocytosis– when the cell membrane surrounds a particle, encloses it, and brings it into the cell. • Endo – take in • White blood cells use this process to exterminate threats in our body

6. Two Types: • Exocytosis – The cell releases a substance within it through its membrane. • Exo - release

7. Higher outside <- Exocytosis Higher inside Endocytosis Low to high concentration, in one of two ways:

8. Endocytosis / Exocytosis Animation • http://www.youtube.com/watch?v=1w10R9lv7eQ

9. REVIEW!! • Slug • http://www.youtube.com/watch?v=PiQkebrCw8U