Ms' Ellen Hellerich

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Wind Your Way Around Your Own DNA

• 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

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Learning Goals

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

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Student Objectives
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Getting Started

• 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

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What do you need?

• 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

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Let's see some DNA!

• Obtain and label a plastic cup with your name

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2. Fill your cup with approximately 5 ml/1
Teaspoon of Gatorade
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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!
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4. Slowly pour enough cheek water to make the
test tube half full.
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5. Add 1 ml/10 drops of detergent solution into
your test tube and cap the tube.
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6. Gently rock (NOT SHAKE!) the test tube back
and forth to mix the contents, so that bubbles do
not form.
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No Bubbles? Great! Remove the cap and keep the
test tube upright from this point on!
Ellen
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8. Add 5 ml/1 Teaspoon of ice cold ethyl alcohol.
This should almost fill the test tube.
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9. Observe the interface for the precipitation of
the DNA. Small bubbles with white strings
attached will slowly make their way to the top of
the alcohol. This is DNA!
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10. Pour contents of test tube back into plastic
cup and dispose of the materials as directed.
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Key Terms
Interface
Precipitate
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Discussion
?
?
Did everyones DNA look the same?
Why did some people have more DNA?
?
What would have happened if you had been chewing
gum?
?
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Want some more Ideas?
Try using warm water to bathe the test tube until
it is 55C
What other organisms can you extract DNA from?
Experiment w/different concentrations of
Gatorade/detergent
Try different swishing methods
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References

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