1. Types of Transport Across Cell Membranes

2. Simple Diffusion Brownian Movement
Requires NO energy, passive movement
Molecules move from area of HIGH to LOW concentration
Random movement
of particles
Brownian Movement

3. Diffusion of Liquids

4. Diffusion through a Membrane
Cell membrane
Solute moves DOWN concentration gradient (HIGH to LOW)

5. Diffusion across a membrane Semipermeable membrane
Osmosis
Diffusion of WATER across a membrane
Moves from HIGH water concentration to LOW water concentration
Diffusion across a membrane
Semipermeable membrane

6. Three types of conditions
Isotonic solutions
When the amount of solutes is equal inside and outside of cell (cell will stay the same)
Hypotonic solution
When solutes outside are lower than inside cell (cell will swell) * more water outside
Hypertonic solution
When solutes outside are higher than inside cell (cell will shrink) * more water inside cell

7. Cell in Isotonic Solution
10% NaCL 90% H2O
ENVIRONMENT
CELL
NO NET MOVEMENT
10% NaCL
90% H2O
What is the direction of water movement?
equilibrium
The cell is at _______________.

8. Cell in Hypotonic Solution
10% NaCL 90% H2O
CELL
H2O
20% NaCL
80% H2O
What is the direction of water movement?

9. Cell in Hypertonic Solution
15% NaCL 85% H2O
ENVIRONMENT
CELL
H2O
5% NaCL
95% H2O
What is the direction of water movement?

10. Cells in Solutions

11. NO NET MOVEMENT OF H2O (equal amounts entering & leaving)
Isotonic Solution
Hypotonic Solution
Hypertonic Solution
NO NET MOVEMENT OF H2O (equal amounts entering & leaving)
CYTOLYSIS
PLASMOLYSIS

12. Osmosis in Red Blood Cells
Isotonic
Hypertonic
Hypotonic

13. Hypertonic
Isotonic
Hypotonic
Hypertonic
Isotonic
Hypotonic

14. Moving Things in and out of Cells
Cellular Transport

15. A.Passive Transport (2 types) 1.Simple Diffusion
Doesn’t require energy
Moves high to low concentration (Down)
Example: Oxygen or water diffusing into a cell and carbon dioxide diffusing out.

16. 2. Facilitated diffusion
Doesn’t require energy
Uses transport proteins to move high to low concentration
Examples: Glucose or amino acids moving from blood into a cell.

17. 2.Facilitated Diffusion
Molecules will randomly move through the pores in Channel Proteins.

18. 2.Facilitated Diffusion
Some Carrier proteins do not extend through the membrane.
They bond and drag molecules through the lipid bilayer and release them on the opposite side.

19. B.Active Transport Requires energy or ATP
Moves materials from LOW to HIGH concentration
AGAINST (up) concentration gradient

20. Sodium-Potassium Pump
3 Na+ pumped in for every 2 K+ pumped out; creates a membrane potential

21. Large molecules move materials into the cell by.
1. Endocytosis Moving the “Big Stuff”
Large molecules move materials into the cell by.

22. Endocytosis Cell forms an invagination
Materials dissolve in water to be brought into cell
Called “Cell Drinking”

23. 2. Exocytosis The opposite of endocytosis is exocytosis
2.Exocytosis The opposite of endocytosis is exocytosis. Large molecules that are manufactured in the cell are released out of the cell through the cell membrane.
Inside Cell
Cell environment

24. Exocytosis