1. 1 PASSIVE TRANSPORT ACROSS A MEMBRANE

2. Passive & Active Transport Overview Cell Transport Passive Transport DiffusionOsmosis Facilitated Diffusion Active Transport Carrier Proteins Endocytosis Exocytosis no cell energy needed molecules move with the concentration gradient (high to low) due to random molecular motion cell energy needed molecules move against the concentration gradient (low to high) molecules enter or leave one at a time many molecules enter or leave together i.e. bulk transport

3. Passive Transport Diffusion: even spreading of molecules from an area of high concentration to an area of lower concentration move with the concentration gradient Osmosis : diffusion of water molecules across a selectively permeable membrane move with the concentration gradient

4. Isotonic solution: contains the same concentration of solute as an another solution Hypotonic solution: contains a low concentration of solute relative to another solution Hypertonic solution: contains a high concentration of solute relative to another solution http://www.tvdsb.on.ca/WESTMIN/science/sbi3a1/cells/Osmosis.htm

5. Solution IsotonicHypotonicHypertonic Cell Types 1.Plant Cell 2. Animal Cell same amount of water enters & leaves no change loss of turgor pressure plant wilts plasmolysis water enters the cell by osmosis turgor pressure develops helps support plant water leaves the cell by osmosis no change cytolysis – cell burstscell shrinks

6. H 2 O leaves by osmosis whole cell shrivels H 2 O enters by osmosis cell membrane can’t withstand pressure bursts - cytolysis Red Blood Cells ∴ all intravenous medication must be: isotonic or blood cells will die

7. LETS SEE WHAT YOU REMEMBER???

8. 1. Which bag would you predict to show the least change in mass at the end of the experiment? a. The bag in Beaker 1 b. The bag in Beaker 2 c. The bag in Beaker 3 d. The bag in Beaker 4 e. The bag in Beaker 5 Correct C

9. 2. After the experiment has run for 30 minutes, which bag loses the most mass which gains the most mass? List the bag that gains the most mass first. a. 1, 2, 3, 4, 5 b. 1, 5, 2, 3, 4 c. 4, 3, 2, 5, 1 d. 3, 2, 1, 4, 5 e. 2, 1, 5, 3, 4 Correct e

10. Passive Transport turgor pressure pushes cell membrane against cell wall cell becomes turgid - stiff loss of turgor pressure cell membrane pulls away from cell wall cell becomes flaccid plasmolysis

11. Passive Transport 1. directly through phospholipid bilayer ex. O 2 CO 2 H 2 O 2. protein channels charged ions & water ex. Na +, Ca 2+, K+, Cl - 3.carrier protein called facilitated diffusion larger molecules ex. glucose, amino acids higher concentration outside 123

12. Facilitated Diffusion a) molecule bounces into a specific carrier protein b)carrier protein binds molecule d)carrier protein resumes its shape used for molecules that are too big to pass directly through cell membrane or protein channel high concentration outside lower concentration inside c)carrier changes shape & flips over, bringing molecule into cell

13. Cell Transport Overview Single Molecules facilitated diffusion protein channel

14. VIDEO

15. Homework Page 64 # 1 – 8 Quiz tomorrow on nutrients and enzymes Time to ask questions