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
Student Objectives 2. To prepare a solution containing their DNA. 1. Precipitate their DNA to make it visible. 3. 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.
Obtain and label a plastic cup place your name on the cup
Let's see some DNA! Mr. Smullen
2. Fill your cup with approximately 5 ml/1 Teaspoon of Gatorade ® Mr. Smullen
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. Mr. Smullen
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! Mr. Smullen
8. Add 5 ml/1 Teaspoon of ice cold ethyl alcohol. This should almost fill the test tube.
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!
10. Pour contents of test tube back into plastic cup and dispose of the materials as directed. “ Super Intern” Mr. Smullen