| Coach White's Virtual Laboratory | ||||
| Home Page Home Link Photosynthesis Lab DNA Extraction Lab Picture Gallery |
DNA Extraction Lab Procedure First, you need to find something that contains DNA. Since DNA is the blueprint for life, everything living contains DNA. For this experiment, we like to use green split peas. But there are lots of other DNA sources too, such as: spinach, chicken liver, onions, broccoli, banana, and kiwi. Put in a blender: Your DNA source (about 100ml or 1/2 cup of split peas), A large pinch of table salt (less than 1ml or 1/8 teaspoon), Twice as much cold water as the DNA source (about 200ml or 1 cup). Blend on high for 15 seconds. The blender separates the pea cells from each other, so you now have a really thin pea-cell soup. Because this step is pretty messy, certain sources of DNA should not be used, such as: Your family pet, Fido the dog, Your little sister's big toe, and bugs you caught in the yard. And now, those 3 easy steps: 1. Pour your thin pea-cell soup through a strainer into another container (like a measuring cup). How much pea soup do you have? Add about 1/6 of that amount of liquid Detergent (about 30ml or 2 tablespoons) and swirl to mix. Let the mixture sit for 5-10 minutes. Pour the mixture into test tubes or other small glass containers, each about 1/3 full. Try one of these detergents or whatever you have on hand. Why am I adding detergent? 2. Add a pinch of enzymes to each test tube and stir gently. Be careful! If you stir too hard, you'll break up the DNA, making it harder to see. Use meat tenderizer for enzymes. If you can't find tenderizer, try using pineapple juice or contact lens cleaning solution. What is an enyme? 3. Tilt your test tube and slowly pour rubbing alcohol (70-95% isopropyl or ethyl alcohol) into the tube down the side so that it forms a layer on top of the pea mixture. Pour until you have about the same amount of alcohol in the tube as pea mixture. DNA will rise into the alcohol layer from the pea layer. You can use a wooden stick or other hook to draw the DNA into the alcohol.
This information comes from the Genetic Learning Center at the Eccles
Institute of Human Genetics |
|
