1. Purple Onion Microscope Lab An investigation in osmosis

2. Review the Lab Directions Obtain all lab materials. –Make sure you have a purple section of the onion skin. –Even though the directions call for two eye droppers and two solutions, we will only be using one of each. Read through Lab Directions Steps 1–8.

3. Scenario 1 After you have focused the microscope on low power, move to high power and begin to sketch your onion cells for Scenario 1. Remember to record three observations. If you are having trouble finding the onion cells, here is an example:

4. Scenario 2 If you are having trouble finding the onion cells, here is an example: After adding the salt solution, sketch the onion cells. Remember to record three observations.

5. Scenario 3 Placing distilled water on the slide will result in the onion cell expanding. Draw this picture for Scenario 3 and record three observations.

6. Clean Up Turn off microscope and make sure it is unplugged. Wet paper towel with water and wipe down slide and cover slip. Throw away onion skin and paper towel. Return all other materials.