Purple Onion Microscope Lab

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 18.

3
Scenario 1
If you are having trouble finding the onion
cells, here is an example

• 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.

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.