1. Diffusion & Osmosis

2. A concentrated solution is a _______ solution &
Bellwork November 7, 2012
A concentrated solution is a _______ solution
&
a weak solution is a ______ solution.
Fill in the blanks with Strong or dilute

3. Diffusion is the Net movement of molecules in a liquid or gas spreading out… … from regions of high concentration… …Down a concentration gradient … to regions of low concentration… …until the particles are evenly spread out.

4. Concentration Gradient
– difference between concentration of molecules in 2 places

5. Factors that affect Diffusion How or what would make diffusion faster or slower
Distance the molecules have to travel –
2. Concentration gradient -
3. Surface area –
4. Temperature -
5. Size of molecule -

6. Factors that affect diffusion
Distance the molecules have to travel –
shorter distance faster
2. Concentration gradient
higher faster
3. Surface area –
more surface area more diffusion
4. Temperature -
hotter diffuses faster
5. Size of molecule -
smaller diffuse faster than big

7. Relate the relevance of diffusion to living organisms
diffusion of oxygen and carbon dioxide into and out of a plant leaf or across the surface of alveoli in lungs

8. ? Bellwork Nov. 8, 2012
On page 39 in your notebook, discuss the factors that were manipulated in the chocolate diffusion lab and how they affected the rate of diffusion.

9. Predict
In the next 2 minutes in your notebook predict & draw an illustration of what will happen when a concentrated sugar solution is placed in a water solution. As a group…Come up with a prediction on your white board.

10. This is described as Partially Permeable
Cell Membrane
… has tiny holes it which allows small molecules to pass through but not larger ones
This is described as Partially Permeable

11. Osmosis
…is the diffusion of water from a dilute solution(high conc. of water) into an area of low conc. of water through a partially permeable membrane.

12. In other words
Water wants to be equal …so it goes from where water is higher to where water is lower through a cell membrane… Until water is equal

13. Flaccid cell isotonic cell Turgid cell
Biology book page -
Flaccid cell isotonic cell Turgid cell

14. Explain what happened to the sugar solution
Explain what happened to the sugar solution. Use the terms: osmosis, water Partially permeable

15. Plant cells
Hypotonic isotonic hypertonic
Plasmolysed

16. Turgid vs Flaccid
When water enters a plant cell it swells up because the sap vacuole holds the water and salts and sugars. This swelling pushes on the cell wall and the cell becomes Turgid. When the water leaves the cell the sap vacuole starts to shrink which pulls the cell membrane away from the cell wall and the plant wilts. The cell is called flaccid when it is shrunk in this fashion .

17. PLASMOLYSED
Cytoplasm moves away from cell wall and Plant cells shrink in size and mass