1. TODAY’S AGENDA P.O.D: Make an initial observation of the fish tank before the food coloring is added. Then predict what will happen when a fish tank filled with water receives 5 drops of red food coloring on the right side and 5 drops of blue coloring on the left side. Food coloring demonstration Review Cell Organelles Notes on the cell membrane, diffusion and facilitated diffusion Final observations on food coloring demonstration HW: Write a page paper about what you saw in the food coloring demonstration

2. CELL TRANSPORT Student learning goals: At the conclusion of the lesson students will be able to define diffusion and state the role of the cell membrane during passive transport. Students will also be able to analyze what they observed happening to the food coloring and connect it to diffusion.

3. Why are cells small?  Limited because organelles need to be close to cell membrane  Smaller = more efficient transfer of materials

4. Cell Organelle Review http://www.youtube.com/watch?v=-zafJKbMPA8

5. Cell Membrane  Composed of a lipid bilayer  Selectively permeable  Regulates what enters & leaves cell  Assists in homeostasis

6. Phospholipids  Subunit of cell membrane  Heads love water – “hydrophilic”  Tails don’t like water – “hydrophobic”

7. Heads Tails

8. Water: Inside & Outside the Cell

9. Fluid Mosaic Model  Cell membrane is flexible ( fluid )  Composed of many parts ( mosaic )

10. Two layers of phospholipids

11. Channel Protein  Molecules with a specific shape allowed to pass through

12. Receptor Protein  Receives and transfers information from outside to inside cell

13. Marker Protein  “Name tag” of cell  identifies type of cell  Important in organ transplants

14. Cell Membrane  Cells need to be able to move substances across the cell membrane  Two Ways: 1. Passive Transport 2. Active Transport

15. Passive Transport  Movement of materials across the cell membrane without using energy from the cell  3 Types- Diffusion, Osmosis & Facilitated Diffusion

16. Diffusion  Movement of molecules from an area of higher concentration to an area of lower concentration

17. Diffusion

18. Facilitated Diffusion  Diffusion using channel proteins in cell membrane  Does NOT require energy  Used for molecules that are large (Ex. Glucose)

19. Facilitated Diffusion