1. For the Teacher
Students will learn the basics of osmosis and diffusion and understanding how it affects plants under different conditions
Students will be able to explain and discuss the different solutions a plant could be exposed to and the result of such solution
Prior to starting an experiment on osmosis using gummy bears ask a few critical thinking questions/ check for understanding. Have them write in a blank piece of paper and turn it in to you to see if they truly understand what's been discussed.
Standards:
G. Plant and Soil Science Pathway
G.2.0
G2.2

2. Going with the Flow: Osmosis
By Andrea Melano

3. What we will accomplish today…
Understand the process of osmosis and diffusion
Be able to explain the effect of osmosis in plants with different solutions
Hypotonic
Hypertonic
Isotonic

4. Osmosis
Process in which a solute passes through a semipermeable membrane.
Other Molecule
High
Solute- a part of a solution: in a solution, the dissolving substance(material) is called a solvent whereas the dissolved substance(material) is called a solute
Semipermeable membrane: a membrane that allows certain types of molecules to pass through but blocks others.
Membrane: a cell structure that separates the interior(inside) of all cells from the outside environment
Low
H20

5. A solute is a part of a solution which dissolves.
A semipermeable membrane is like a wall on the cell that blocks some molecules and allows others in

6. The solute travels from an area of high concentration to an area with low concentration.
This process of moving from high to low concentration is called diffusion

7. Hypotonic State: a state in which there are less solute molecules outside the cell. This causes water to move into the cell and that object will expand
"HYPO" means less
"HYPER" means more

9. Isotonic state: a solution with an equal concentration to another solution.

10. How does this apply to Plants?
Plants use osmosis to absorb water and nutrients from the soil.
Ask if any one has any ideas.

11. What will happen to a plant in Hypertonic Solution
What will happen to a plant in Hypertonic Solution? Discuss with a partner.
Give them a few minutes to brainstorm

12. In a hypertonic solution a plant will shrivel up.
Water inside the cells is drawn out
Vacuoles and Cytoplasm shrink in size
This causes a lack of structure
Vacuoles like storage bubbles found in cells. They store water nutrients and waste
Cytoplasm – what gives the plants their structure( they also have other functions)- think of empty balloon. As you fill it with water it begin to take shape.

13. What will happen to a plant in Hypotonic Solution
What will happen to a plant in Hypotonic Solution? Discuss with a partner.
Give them a few minutes to brainstorm

14. In a hypotonic solution a plants cells will fill up to maximum capacity.
A strong cell wall stops the cells from bursting
The plant will become turgid
Hypotonic solution has a lower salt concentration than in normal cells of the body and the blood. As opposed to an isotonic solution or a hypertonic solution.

15. What will happen to a plant in an isotonic solution?
Discuss with a partner?

16. In an Isotonic solution the plant will remain in equilibrium.
Nothing will happen
No movement of water into or out of the cell

17. Checking for Understanding: Via the Gummy Bear Family
Next week we will do an experiment on osmosis using gummy bears Lets take some time to discuss what we believe would happen to these gummy bears?
Checking for Understanding: Via the Gummy Bear Family
Gummy bears are basically jell-o
They are made by heating up similar ingredient at gelatin with hot water. Once molded they take out all of the H2O from the gummy bear. The gummy bear is therefore a low concentration area.
Momma Bear is in a solution of water
Papa Bear is in a solution of Salt Water
Baby Bear is in a solution of distilled water

18. Gummy bears have a very low concentration of H2O
Momma Gummy Bear has been placed in a cup of water
What will happen to momma gummy bear and why?

19. Once again gummy bears have a very low concentration of H2O
Papa Gummy Bear has been placed in a cup of salt water.
Hint: Salt molecules are much smaller then the molecules in the gelatin.
Where are the highest concentrations of solute?
What will happen to papa gummy bear and why?

20. Baby Gummy Bear has been placed in a cup of distilled water
By now you should know that gummy bears have a very low concentration of H2O
Baby Gummy Bear has been placed in a cup of distilled water
Distilled water is pure water with no impurities.
What will happen to baby gummy bear and why?
Impurities is like a contaminant. Organisms or bacteria. Minerals
Ex. aluminum and lead are impurities frequently found in tap water

22. Works Cited
Hitchen, Becky. Hypertonic, hypotonic and isotonic effects on plants and animal cells Wiki Spaces. <
Kishe. Youtube- Diffusion and Osmosis. September 29, Mr. Kish's Science Channel. October 5, <
What Is a Semipermeable Membrane? Wise Geek. October 5, <
What Is Osmosis? Wise Geek. October 5, <