1. Finishing the Lab Report
Diffusion and Osmosis
Finishing the Lab Report

2. **Go get your group’s three cups and bring them to your table
Do Now
A baby sitter faces first-degree murder charges after she is accused of making a toddler drink so much water it killed her. Police say Nancy Gayoso (pictured), 34, forced 3-year-old Rosita Gonzalez to drink excessive amounts of water when she was babysitting on Oct. 14, She was indicted on murder charges Thursday. The Broward County Medical Examiner determined that the child died of water intoxication. How did that happen? Draw a picture of the child’s cells to explain.

3. Introduction The toddler’s cells looked something like this
Is this isotonic, hypertonic, or hypotonic?

4. Review from last class
Which one is H2O moving out? Moving in?

5. Which direction will water move?

6. Osmosis vs Diffusion In osmosis, what is moving? WATER
In diffusion, what is moving?
PARTICLES

7. Osmosis or Diffusion?

8. Osmosis or Diffusion

9. What was the lab about?
We wanted to figure out which solution was hypertonic, hypotonic, and isotonic
To what?
A potato core

10. So… (hypothesis…)
If the solution was isotonic, then the mass of the potato core would ( increase / decrease ) because water would move…
If the solution was hypertonic, then the mass of the potato core would ( increase / decrease ) because water would move…
If the solution was hypotonic, then the mass of the potato core would ( increase / decrease ) because water would move…

11. Diffusion and Osmosis: Day 2
Collect your remaining data by carefully measuring the length and mass of your remaining potatoes
Calculate the “Change” by subtracting “Day 1” from “Day 2”
Calculate the “% Change” by dividing the “Change” by “Day 1” x 100. (NOTE: Keep any calculations which are negative do not use the absolute value).
Graph the % change in mass for the class avg.

12. Solution A
Solution B
Solution C
Day 1
Day 2
Change
Mass
Appearance

13. Part B: Semi-Permeability
1) Sketch, Label and Color the Set-up 
          Be sure to label
Water                
Iodine
Flour                           
Membrane
2) What substances are IN the bag?
3) What substances are OUTSIDE the bag?

14. After 5 mimutes… 4) Sketch, Label and Color the set-up
5) What substances are now IN the bag?
6) What substances are OUTSIDE the bag?
7) How do you know?

15. You Do: Conclusion
Did you observe diffusion or osmosis in the potato core? How do you know?
Into which of the potato cores did water flow? From which of the potato cores did water flow? How can you tell? (Support with data)
Was solution A hypertonic, hypotonic, or isotonic to the potato core? How did you know?
Was solution B hypertonic, hypotonic, or isotonic to the potato core? How did you know?
Was solution C hypertonic, hypotonic, or isotonic to the potato core? How did you know?
Part B:
Dialysis tubing is a semi-permeable membrane – explain why…
How did the tubing act like a cell membrane?