1. Egg Lab CER
Critical Writing

2. *Warm Up* In your journal…
Pick up the paper at the front table.
Begin filling out.
Title page 54: Tonicity practice
Glue at the top of the page.

3. Water concentration is highest in the solution.
There is a lower amount of solute in the solution compared to the cell:
Hypotonic Solution
Because osmosis is a type of diffusion…water will move from areas of high concentration to low concentration.
Remember HYPO means LOW
Therefore, water will move inside the cell.

4. Water concentration is lowest in the solution.
There is a higher amount of solute in the solution compared to the cell:
Hypertonic Solution
Because osmosis is a type of diffusion…water will move from areas of high concentration to low concentration.
Remember HYPER means HIGH
Therefore, water will move out of the cell.

5. Water concentration is the same in the solution as in the cell.
There is an equal amount of solute in the solution compared to the cell:
Isotonic Solution
Because osmosis is a type of diffusion…water will move from areas of high concentration to low concentration.
Remember ISO means SAME or EQUAL
Therefore, water will move back and forth across the membrane at equal rates.

6. Tonicity Practice (pg 54)
With your partner, write your question down on page 54.
Draw a picture showing what is happening.
Describe what type of solution is in the cell, and what type of solution is surrounding the cell.
Describe which way the water will move.

7. Egg Lab Day 1
Egg 1 mass: 80.5 g Egg 2 mass: 85.8 g

8. Egg Lab day 2
Mass egg #1: 81.9g (distilled water egg) Mass egg #2: 40.6 g (corn syrup egg) What happened to the egg placed in distilled water? What caused this change? What happened to the egg placed in corn syrup? What caused this change? What kind of solution is distilled water? What kind of solution is corn syrup?

9. Egg Lab day 2
Critical Writing Needs to be in CER format. Use the next few slides to help you write your CER.

10. Claim
__________________ is the process responsible for the change in mass. Eggs placed in a ___________________ solution will __________________. Eggs placed in a ______________________ will ____________________________.
Word Bank
Osmosis
Hypertonic
Hypotonic
Grow/expand
Shrink/shrivel

11. Evidence
The egg placed in distilled water…..(use your data to indicate the changes in mass) The egg placed in corn syrup…..(use your data to indicate the changes in mass)
Word Bank
Initial mass
Final mass

12. Reasoning
Osmosis is a type of _______________ transport and is the diffusion of _______________. The egg is corn syrup was a _________________ solution causing the water to _______________ the egg resulting in a decrease in mass. The egg is distilled water was a __________________ solution causing the water to _________________ the egg resulting in an ___________________ in mass. Once equilibrium is reached, the water molecules will……Movement of water across the membrane is going down the ____________________ gradient.
Word Bank
Hypertonic
Hypotonic
Passive
Increase
decrease