1. In da Club (~11 min) https://www.youtube.com/watch?v=dPKvHrD1eS4
Cell Transport
In da Club (~11 min)

2. Cell membrane
All cells are surrounded by a flexible barriers = cell membrane
The membrane controls what enter and leaves the cell
It is made of 2 layers of lipid = lipid bilayer

3. Carbohydrates also attach, acting as signal receptors from other cells
proteins are embedded within the lipid bilayer--act as channels or pumps to help get things across the membrane
Carbohydrates also attach, acting as signal receptors from other cells
carbohydrates
proteins

4. Cell wall
Many cells also have a strong layer around the membrane = cell wall
Is for support and protection of the cell
Plants, algae, fungi, and prokaryotes have walls

5. Concentration
The cytoplasm of the cell is a solution of water with many substances dissolved with in it
Concentration refers to the amount of solute within the solution

6. Diffusion Particles constantly move and will spread out
Particles will move from areas where they are more concentrated (crowded) to areas of lower concentration (less crowded)
Diffusion – process of particles moving from high to low concentration

7. Diffusion across membrane
If there is more of a solute on one side of the membrane, the substance will move to the side of lower concentration to “spread out”

8. Equilibrium
When the concentration of the solute is the same throughout the solution, or on both sides of the membrane, it has reached
equilibrium

9. Diffusion of O2 into cell

10. Osmosis permeable-can cross the membrane
impermeable-can not cross the membrane

11. Osmosis is the diffusion of water molecules across the membrane

12. There is more sugar on right side, so amount of water on right is less
Sugar cannot pass, but the water can

13. Water will move until the concentration of the solute “sugar” is equal
The two solutions are then isotonic – same strength

14. The side with the higher concentration of sugar = hypertonic- above strength
The side with the lower concentration of sugar= hypotonic – below strength

15. Affect on cells Cells must balance the movement of water from osmosis
Too much water in or out of cell will kill cell
Animal cells need an isotonic environment

16. Osmotic pressure
Unicellular organisms have “pumps” on membrane-contractile vacuoles
Many have walls to prevent bursting
Cells with walls like a hypotonic environment

17. Facilitated diffusion
When Proteins on the membrane act as “channels” to facilitate, “help” the large molecules to get across, (but still is G to L).
No energy needed

18. Active transport
Cells must sometimes move materials in the opposite direction of diffusion- against the concentration gradient = active transport
Requires energy (LESS TO GREATER!)
Proteins in the membrane can act as ‘pumps’

19. Active transport
ATP= cell energy

20. Sodium potassium pump
Most used pump in animals! ATP is used to do it.

21. Larger material may need to be transported by movements of the cytoplasm itself
Endocytosis – taking material into the cell by folds/pockets formed in the membrane
The pocket then breaks loose from the membrane and is a vacuole
Uses energy

22. Types of Endocytosis phagocytosis pinocytosis
Material taken in is of solid nature
Cell is “eating’
Material taken in is liquid

23. Exocytosis
Vacuole membrane fuses with cell membrane pushing contents of vacuole out of the cell

24. SUMMARY: 1. PASSIVE TRANSPORT (G to L) no energy Diffusion Osmosis
Facilitated Diffusion
2. ACTIVE TRANSPORT (uses energy)
Proteins act as pumps (L to G)
Endocytosis (phagocytosis/pinocytosis)
Exocytosis