An Egg-cellent Egg-speriment -Investigating Osmosis-

Background: Osmosis is the process in which water moves through a cell. You will use a large cell (an egg) to investigate osmosis.

Problem: Which direction will water move (into the cell or out of the cell) in various types of solutions?

Hypothesis: Make your prediction based on the solutions that egg 1 and egg 2 are in. You will have two hypothesis, one for egg 1 and one for egg 2.

Materials: *2 raw eggs *2 cups *measuring tape (or string and ruler) *vinegar *corn syrup *salt *water *food coloring *any solution of your choice Procedure: Day 1 and 2: Measure the circumference (use centimeters) of two raw eggs. Record. Place each in a cup of vinegar. Let it sit for two days. Day 3: Carefully remove and measure circumference. Record. Egg 1 will be your control. Place it into a cup of water. Egg 2 will be your experimental egg. Place egg 2 into a cup of syrup. Let it sit for one day. Day 4: Carefully remove and measure the circumference of both eggs. Record. Egg 1 goes back into the water. Place egg 2 into a cup of water with food coloring. Let it sit for one day. Day 5: Carefully remove and measure the circumference of both eggs. Record. Egg 1 goes back into the water. Place egg 2 into a cup of very salty water. (add salt to warm water and dissolve as much salt as you can) Let it sit for one day. Day 6: Carefully remove and measure the circumference of both eggs. Record. Egg 1 goes back into the water. Place egg 2 into a cup of your chosen solution. Let sit for one day. Day 7: Carefully remove and measure the circumference of both eggs. Record. Now you may throw your eggs away.

Results: Data Tables Egg One EggTwo Liquid Circumference Qualitative Liquid Circumference Qualitative (cm) Observations (What does (cm) Observations (What it look like?) does it look like?) Initial Initial Vinegar Vinegar Water Syrup Water Food Color Water Salt Water Water Your solution:

Graph: Make a bar or line graph showing your data for each egg.

Conclusion: 1. Why was it necessary to place the eggs in vinegar? 2. What is it necessary to have a control group? (Egg 1.) 3. Why do you think osmosis is important for cells? 4. Which types of solutions did water move into the cell? How did you know? 5. Which types of solutions did water move out of the cell? How did you know? 6. What does the movement of water through a cell tell you about the size of a water molecule?

Due date ______EGGSPERIMENT LAB REPORT RUBRIC Points Points Possible Received PROBLEM STATED 5

HYPOTHESIS 5 (Independent & dependent variables included) MATERIALS & PROCEDURE 5 (All steps clearly stated) OBSERVATIONS AND DATA TABLE 10 (Measurement units identified) GRAPHS AND/OR ILLUSTRATION 10 (Title, axes labeled, data points plotted) CONCLUSION 10 (Answers the problem, explains results, complete sentences used) NEATNESS 5

TOTAL GRADE 50