1. Part 1

2. Cell Membrane and Transport

3. What is an Isotonic Solution?
[Water] inside cell = [Water] outside cell
Cell is at equilibrium
Molecules are equally distributed in end
The amount of water entering the cell = the amount of water leaving the cell
95% water
95% water

4. What is a hypotonic solution?
A solution that has MORE water, and LESS solute
The cell can lyse or burst if left in a hypotonic solution
100% water
95% water

5. What is a hypertonic solution?
A solution that has LESS water and MORE solute
The cell will dehydrate
90% water
95% water

6. Which direction does water flow?
Water doesn’t flow at all.
Water flows from an area of low concentration to an area of high concentration.
Water flows from an area of high concentration to an area of low concentration.

7. Lipids Lipids function in: Nonpolar (hydrophobic)
Energy (E) storage,
forming cell membranes,
and as chemical messengers (e.g., hormones)
Nonpolar (hydrophobic)
Made up mostly of Carbon and Hydrogen (with a few Oxygen)

8. Lipids Fats (Triglycerides) Glycerol + 3 Fatty Acids
Saturated = No Double Bonds (solid)
Unsaturated = Double Bonds (liquid) OH OH OH
Ester Bonds OH OH OH

9. Organic Compounds: Lipids: Phospholipids
Glycerol with Phosphate Head + 2 Fatty Acid Chains
Amphiphilic (“Both” “lover”)
Hydrophilic head
Hydrophobic tail
Forms 2 layers in water
Makes up cell membranes
Phosphate
Glycerol
Left-side Activity: Identifying hydrophilic and hydrophobic portions of the membrane.
Fatty Acids

10. Egg lab
Dissolve egg shells
Rinse
Calculate initial mass

11. The Cell Membrane and Diffusion
The plasma/cell membrane is selectively permeable
~only certain substances are allowed to pass through

12. What can and can not pass through the membrane?
CAN PASS THROUGH
Things that can dissolve in fat
Small molecules
Water
CAN NOT PASS THROUGH
Things that can dissolve in water
Large molecules
Ions: Molecules with plus (+) or minus (-) charges
CH2OH OH

13. Part 2

14. Passive Transport 3 types No energy is used
There are three types…
3 types
No energy is used
[High]  [Low] (it’s the natural flow)
This means it goes down a concentration gradient

15. 3 types of Passive Transport
1. Diffusion
2. Osmosis
3. Facilitated Diffusion

16. Diffusion
[High]  [Low]

17. Osmosis

18. Facilitated Diffusion+
Facilitated Diffusion
CH2OH OH
Passive Transport: Facilitated Diffusion

19. This means it goes up or against a concentration gradient
Active Transport
There are three types…
3 types
Energy is used
[Low]  [High]
This means it goes up or against a concentration gradient

20. 3 Examples of Active Transport
1. Protein pumps
2. Endocytosis
3. Exocytosis

21. Protein Pumps
Protein Pumps: proteins use energy to pull or pump materials into or out of the cell to stockpile or store substances the cell needs

22. Different Types of Membrane Proteins (page 77)
SIGNAL/ RECOGNITION
TRANSPORTERS
RECEPTORS
ENZYMES

23. Different Types of Membrane Proteins (page 77)
signal/recognition
Enzymes
receptor
transporter

24. Endocytosis When cells engulf particles into the cell 2 types
Phagocytosis: When a cell wraps part of its membrane around a large particle forming a “pocket” or vesicle
Pinocytosis: The same process, but with smaller particles or liquids

25. Exocytosis A vesicle carrying a substance fuses with the cell membrane
and releases the substance