1. Warm up 10/15 Draw a plasma membrane & Include the following
Label correct parts of the phospholipids hydrophobic and hydrophilic.
Integral proteins
Peripheral proteins
Cholesterol
What does semi-permeable mean?

2. Chapter 4- 5: Notebook #9 (Ws #1: Notebook #8) Textbook pg. 97-102
PASSIVE TRANSPORT
Chapter 4- 5: Notebook #9 (Ws #1: Notebook #8)
Textbook pg

3. Solutions
2 Parts:
Concentration: A measure of how much solute per unit of solvent
ex/ 200mg NaCl / mL H20
Solution =
Solute (that which is dissolved) +
Solvent (the liquid that does the dissolving)
These glasses containing red dye demonstrate qualitative changes in concentration. The solutions on the left are more dilute, compared to the more concentrated solutions on the right.

4. Passive transport Movement across the cell membrane without energy.
What characteristic does the cell membrane have?

5. Diffusion
Movement of molecules from area of high concentration (CONC) to area of low concentration

6. Concentration Gradient
Molecules have kinetic energy
Concentration Gradient: difference between high and low concentration
Molecules move “down” gradient.
Molecules move until they reach equilibrium (when all molecules are evenly spread out).

7. Osmosis Osmosis: special diffusion of water across membrane
A solution is made of a solute dissolved in a solvent (like water).
Direction of movement is dependent on solutes outside cell.

8. Hypotonic
Concentration of solutes is lower outside the cell and water moves into the cell  cell swells

9. Hypertonic
Concentration of solutes is higher outside the cell and water moves out the cell  cell shrinks

10. Isotonic:
Concentration of solutes inside = outside  so no water moves

12. Facilitated Diffusion
Molecules too big to move across the membrane use carrier proteins Ex. Glucose

13. CELL DIVERSITY AND CELL SIZE
Chapter 5 pg

14. Cell shape
Cell shape related to function of the cell

15. Cell size
Surface area to volume ratio decreases with increasing cell size (EX. 6:1 vs 3:1)
Volume increases quicker than the surface area

16. Summary of the Mini-Lab
What was different about the 3 cubes?
What happened when we placed the cubes (model cells) in the solution of NaOH?
Did the NaOH diffuse the same distance?

18. Why is this important to the cell?
Substances cannot get to the center, or out of the center of the cell if it’s too big

19. What does this mean for the cell?
The bigger the volume the less surface area
not enough surface area to meet the needs of the increasing volume
distance to center increases as cell increases
Difficulty exchanging materials (such as nutrients, oxygen, and waste products) across the cell

20. ACTIVE TRANSPORT
Chapter 5 pg

21. Active Transport Requires energy
Molecules move from an area of low concentration to an area of high concentration
Move against the concentration gradient

22. Membrane pumps

23. Carrier proteins that are active are called pumps.
Protein binds to a specific molecule.
Protein transfers the molecule to the other side.
Sodium-Potassium Pump: transports Na+ and K+ against (not down) gradient
3 Na+ out and 2 K+ in

24. Endocytosis and Exocytosis
Used to move very large molecules in and out of the cell

25. Endocytosis Ingest large molecules into cell
Material is engulfed by cell membrane.
Membrane makes a pouch.
Pouch then pinches off and makes a vesicle.
Vesicle binds with lysosome.

26. Phagocytosis
A form of endocytosis in which immune cells attack and ingest bacteria

27. Exocytosis
(the reverse of endocytosis) moving large particles out of the cell