1. March 22, 2010 What is diffusion? Osmosis? What is passive transport?
Describe the makeup of the cell membrane. What types of cells have one?

3. Egg Demo 24 hrs in Vinegar 24 additional hours in vinegar
Dissolve shell
24 additional hours in vinegar
Egg increases in size
12 hrs in corn syrup
Egg decreases in size

4. Osmosis: Types of solutions
Hypotonic
Outside solution has less solute than inside (less dissolved particles, more water)
Water moves INTO cell
Cell expands
Cell may burst (lysis)
Egg and vinegar

5. Osmosis: Types of solutions
Hypertonic
Outside solution has more solute than inside (more dissolved particles, less water)
Water moves OUT of cell
Cell shrinks
Egg and Corn Syrup

6. Osmosis: Types of solutions
Isotonic
Outside solution and inside solution are equal concentrations
Water moves IN AND OUT of cell at equal rates (dynamic equilibrium)
Cell is unchanged

9. Purple Onion Lab
Read the intro and answer the prelab questions before starting
You need small, thin pieces of OUTER LAYER of onion

10. Active Transport Transport into/out of cell that requires using energy
Can be for big molecules needing to enter/exit
Can be for molecules needing to move against the concentration gradient (ex. move from low concentration to high concentration, they are FORCED to move!)

11. Being Forced to Move
Cell membrane protein pumps use energy to pump things in a direction they don’t want to go
Protein Pumps

12. Big Molecules Endocytosis
Cell membrane wraps around molecule and forms a bag (vessicle) around molecule
Vessicle is broken down inside the cell and then molecules move around to where they are needed
Phagocytosis = cell eating
Pinocytosis = cell drinking

13. Big Molecules Exocytosis
Vessicle with trash molecule inside cell travels toward cell membrane
Vessicle becomes part of cell membrane and opens to outside of cell, releasing it’s contents
Active Transport Video
Amoeba Feeds