1. Vocab Solute – stuff we want to dissolve
Solvent – substance in which something dissolves
Concentration – amount of a solute dissolved in a given volume of solution
A lot = concentrated
A little = dilute

2. Passive transport No energy needed
Particles move from high concentration to low concentration
Particles flow until equilibrium is reached
No change in concentration on each side
Diffusion = particles moving across membrane
Osmosis = water moving across membrane

4. Diffusion and Membrane
Membrane has selective permeability
Polar/nonpolar regions on lipid bilayer
Cannot pass through:
Ions (salts dissolved in water)
Hydrophilic molecules (glucose)
Macromolecules

5. Facilitated Diffusion
Proteins in membrane move particles across

6. Facilitated Diffusion
Carrier proteins
Change shape

7. Osmosis
Diffusion of water across membrane

8. Osmosis
Isotonic – concentration of solute is the same inside and outside cell
Water enters and leaves at same rate

9. Osmosis
Hypotonic – concentration of solute is greater inside the cell, more water outside cell
Cells gain water
Animal cells can burst
Cell wall prevents plant cells from rupturing
Turgor pressure supports the cell
A cell under pressure is turgid

10. Osmosis
Hypertonic – concentration of solute is greater outside the cell
Cells lose water
Animal cells shrivel up
Plants: membranes pulls away from the cell wall
The cell wall is rigid and does not shrink

12. Active Transport Substances moving from low to high concentrations
Need energy
Use proteins in membrane

13. Na/K ATPase Pump Found in animal cells
Helps maintain levels of sodium and potassium
Uses energy (ATP) to move 3 Na ions out of the cell and 2 K into the cell
High levels of sodium on outside creates a gradient

15. Coupled Transport
Linked, simultaneous transport of two substances across a cell membrane
Create a high concentration gradient on 1 side
Protein channels open & allow other particles (sucrose/sugar) to move across membrane
Spend very little energy

17. Transport of Large Particles
Endocytosis –brings substance into cell

18. Transport of Large Particles
Exocytosis – expels stuff from cell
waste, substances (hormones) produced by cell

19. In passive transport, particles move from what to what concentration?
Agenda for Tuesday Nov 22nd
Finish notes
Finish lab
Osmosis worksheet

20. What is wrong with the cartoon?
Agenda for Friday Nov 20th
Go over cell worksheets
Finish gummy bear lab
Finish notes
Osmosis practice sheet
Test Tuesday