2. Which of the following is NOT true about unicellular organisms?
A) They are simple organisms
B) They are made of only one cell
C) They do not contain a nucleus
D) They can do things that multicellular organisms need trillions of cells to do

3. Fill in the blanks…
A) This organelle controls entry into the cell.____________________
B)This organelle is involved in photosynthesis. ____________________
C) This organelle is used to convert energy for use by the cell. ____________________
D) This organelle provides support for the cell.________________________________ _______________________

4. 2.4 How Substances Move Into & Out of Cells
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2.4 How Substances Move Into & Out of Cells
Objectives:
1) You will be able to describe an overview of how substances move in & out of the cell
2) Have a lab opportunity to see the results of osmosis
Why did God make only one Yogi Bear? Because when he tried to make a second one he made a Boo-Boo.

5. WARNING! The following material can be complicating.
You NEED to stay focused otherwise you will get lost very easily
Lab Demo
2 types we’ll be talking about…

6. Copy This Down
1) Diffusion
Movement of particles of a substance from an area of higher concentration to an area of lower concentration
It’s a balancing out process of the particles
No energy required

7. Diffusion Demo

8. Diffusion Demo
Diffusion from a Sealed Container

9. Diffusion in the Real World…

10. 2) Osmosis
Not Spelt Ozzmosis…

11. Osmosis Special kind of diffusion
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Osmosis
Special kind of diffusion
Diffusion of water through a selectively permeable membrane
So what does this mean?
Water particles are small enough to diffuse through the cell membrane with ease, depending on the concentration gradient (H  L)
What’s the big deal?
Osmosis is vital to the survival and health of cells

12. Selectively permeable
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Selectively permeable
A membrane with very small openings that allow particles of some substances, but not others, to pass through. (Based on size)

13. For your reference…
A permeable membrane allows all materials to go in & out
Like an open door
An impermeable membrane does not allow anything in or out.
Like a wall

14. Diffusion & the Cell Membrane
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Diffusion & the Cell Membrane
Particles of many substances move in & out of cells by diffusion
However, the cell membrane acts like a filter with its tiny openings, allowing some particles to go through if they are small enough (I.e. semi-permeable!)
Cell Demo
Iodine particles are small enough to enter the Ziploc bag. Cornstarch particles are too big to leave the Ziploc bag.

15. Example A = Water = Solute A Cell Membrane Outside of Cell
Inside of Cell

16. Example A- Process = Water = Solute A Cell Membrane Outside of Cell
Inside of Cell
High Water Concentration
High Solute A Concentration

17. Example A- Process = Water Cell Membrane Outside of Cell
Inside of Cell
High Water Concentration
Low Water Concentration

18. Example A- Process = Solute A Cell Membrane Outside of Cell
Inside of Cell
Low Solute A Concentration
High Solute A Concentration

19. Example A- Result = Water = Solute A Cell Membrane Outside of Cell
Inside of Cell

20. Example B = Solute A = Solute B Cell Membrane Outside of Cell
Inside of Cell
High Concentration of solute A
High Concentration of solute B

21. Example B Process = Solute A Cell Membrane Outside of Cell
Inside of Cell
High Concentration of solute A
Low Concentration of solute A

22. Example B Process = Solute B Cell Membrane Outside of Cell
Inside of Cell
Is there movement inside the cell?
No! Because the openings are too small!
Low Concentration of solute B
High Concentration of solute B

23. Example B Result = Solute A = Solute B Cell Membrane Outside of Cell
Inside of Cell

24. Example C = Solute A = Solute B = Solute C Cell Membrane
Outside of Cell
Inside of Cell

25. Is there diffusion of Solute A? Which Way?
= Solute B
= Solute C
Cell Membrane
Outside of Cell
Inside of Cell

26. Is there diffusion of Solute B? Which Way?
= Solute A
Is there diffusion of Solute B? Which Way?
= Solute B
= Solute C
Cell Membrane
Outside of Cell
Inside of Cell

27. Is there diffusion of Solute C? Which Way?
= Solute A
Is there diffusion of Solute C? Which Way?
= Solute B
= Solute C
Cell Membrane
Outside of Cell
Inside of Cell

28. Is there diffusion of the nucleus? Which Way?
= Solute A
Is there diffusion of the nucleus? Which Way?
= Solute B
= Solute C
Cell Membrane
Outside of Cell
Inside of Cell

29. Is there diffusion of the mitochondria? Which Way?
= Solute A
Is there diffusion of the mitochondria? Which Way?
= Solute B
= Solute C
Cell Membrane
Outside of Cell
Inside of Cell

30. Osmosis…a little more detailed
Osmosis in plant and animal cells
Plant cells contain cell walls, animal cells do not
So?
If water rushes into a plant cell, it becomes turgid
If water rushes into an animal cell, it bursts!
If water leaves a plant cell, it becomes flaccid
If water leaves an animal cell, it shrinks

31. Osmosis in Us…

32. 3 Terms that you will see in high school
(and could help you for lab reports…)

33. 1) Isotonic
A balance of water going in & out of cell

34. 2) Hypertonic Solution Solution with high concentration of solutes
Salt water solution
Water leaves the cell, and it shrivels
Potentially fatal

35. 3) Hypotonic Solution Solution with the lower concentration of solutes
Distilled water solution
Water enters the cell, and the cell swells
Potentially fatal

38. Summary Cells need an optimal amount of water concentration
There needs to be a balance inside & outside of the cell
If too much water enters and/or leaves the cell, the cell may die

39. Looking at cells that are hypotonic, isotonic, hypertonic!
LAB TIME
Looking at cells that are hypotonic, isotonic, hypertonic!

40. Homework!
Check & Reflect
P. 119
# 1,2,3,4,5
Due next class