1. Warm Up (Silent) 1/28 What two molecules make up the phospholipid bilayer?

2. The Cell Membrane Hydrophobic Hydrophilic

3. All the Parts of the Membrane

5. The Blob!!

6. ALL cells are microscopic! Cells never get as big as the Blob. Cells can’ t be big because…….Surface area won’ t allow enough material to enter ( O2, water, food) to keep the cell interior alive.

7. Cell Membrane Questions Answer the questions on the handout. Use your notes to help you answer the questions.

8. DRAW a portion of the cell membrane on a plain piece of paper. It should be NEAT, FREEHAND, LABELED, AND COLORED. Use the picture on page 78 of the blue book as a pattern

9. Getting through the Membrane

10. Candy Corn Membrane!

12. The Membrane is Selectively Permeable Selective = Chooses Permeable = Passes through The membrane chooses which molecules pass through

13. Concentration Just like people, molecules don't like to be crowded. Concentrated = Crowded

14. Diffusion - Spreading Out Diffusion - molecules naturally move from high concentrated areas to low concentrated areas. Equilibrium - when molecules are evenly spread out.

15. Osmosis Water molecules also doesn't like to be crowded. Osmosis - Movement of water from high concentration of water to a low concentration of water, across a cell membrane.

16. Osmosis Problems 1. Elevator = 80% capacity of people 2nd Floor = 5% capacity of people 2. Beaker = 60% water, 40% salt Dialysis Tube = 20% water, 80% salt 3. Beaker = 10% water, 90% sugar Egg = 60% water, 40% other molecules 4. Beaker = 100% water Egg = 50% water, 50% sugar

17. Osmosis Problems 1. Elevator = 80% capacity of people 2nd Floor = 5% capacity of people Will claustrophobic people move into or out of the elevator when it stops at the 2nd floor? 2. Beaker = 60% water, 40% salt Dialysis Tube = 20% water, 80% salt Will water move into the tube or out of the tube? 3. Beaker = 10% water, 90% sugar Egg = 60% water, 40% other molecules Will water move into the egg or out of the egg? 4. Beaker = 100% water Egg = 50% water, 50% sugar Will water move into the egg or out of the egg?

18. Osmosis in Red Onions (Plant Cells)

19. Demo Egg in Vinegar! Celery in water and salt water Dialysis tubing and starch solution

20. Osmosis worksheet Answer the questions on the handout. Use your notes to help you answer the questions.