Ms. Ellen Hellerich
Nebraska Agriculture in the Classroom
Ms. Marsha Purcell
American Farm Bureau Foundation for Agriculture
Edited by
Debra Spielmaker
Utah Agriculture in the Classroom

1. To provide students with an understanding that cells (and all living things) contain DNA
2. DNA is a physical structure that can be seen with an unaided eye

To prepare a solution containing their DNA.
Precipitate their DNA to make it visible.
Compare the DNA samples from others in the class to see that at this level, DNA looks the same no matter where it comes from.

• DNA is found in the cells of all living things
• Students will be able to see their own DNA protein strands
• The solutions work together to release the DNA strands from the cell membranes
• Alcohol is added to the solution to precipitate the DNA

 Distilled/Bottled Water
 3 oz. Plastic Cup
 Small test tube w/cap or plastic tube w/lid from a florist
 1 Tsp. dish soap/shampoo mixed with 3 Tsp. water
 1 Tsp. Gatorade ®
 Very Cold Ethyl Alcohol (91% or greater, keep on ice)
 Eye Droppers or disposable pipettes
 Paper Towels for clean-up J

1. Obtain and label a plastic cup with your name
Erin Fay
J

2. Fill your cup with approximately 5 ml/1 Teaspoon of Gatorade
®
Erin Fay
J

3. Swish the Gatorade ® in your mouth for no less than 30 seconds then return your “cheek water” to your cup.
Remember to rub your tongue on the inside surface of your cheeks to help dislodge more cells!

4. Slowly pour enough “cheek water” to make the test tube half full.
Erin Fay
J

5. Add 1 ml/10 drops of detergent solution into your test tube and cap the tube.

6. Gently rock ( NOT SHAKE!
) the test tube back and forth to mix the contents, so that bubbles do not form .

No Bubbles?
Great! Remove the cap and keep the test tube upright from this point on!
Ellen

8. Add 5 ml/1 Teaspoon of ice cold ethyl alcohol. This should almost fill the test tube.

“Super Intern”
Erin Fay
J

Why did some people have more DNA?

 St. Louis Science Center
 UIUC – Hughes Biotechnology
Education and Outreach Program