Strawberry & Banana DNA Extraction

1. Strawberry & Banana DNA Extraction

2. Problem: • Is there DNA in the food we eat? • If so, will it be the same for the banana and the strawberry? • What do you expect it will look like? *Please answer these three questions in the hypothesis section of your worksheet

3. Problem: • Is there DNA in the food we eat? • If so, will it be the same for the banana and the strawberry? • What do you expect it will look like? *Please answer these three questions in the hypothesis section of your worksheet

4. Hypothesis: What did you come up with for your hypothesis?

5. Materials: • Chilled isopropanol alcohol • Cup of water • Table spoon of salt • Dawn liquid detergent • Test tube • Funnel • Mixer • Wood Skewer • Cheese cloth • Cup • Strawberry or banana • Small Ziplock bag • Measuring Spoons (Tbsp)

6. Procedures: + + = • Step 1: Mix salt, water, & detergent together in a cup and set aside

7. 2: Place strawberry (or banana) inside plastic baggy and remove all the extra air before sealing • 3: Mush the strawberry (or banana) in the bag for approx 2 mins using your fingers • 4: Add approx. 3 Tbsp of extraction liquid to bag • 5: Remove air, seal bag and mush mixture for another minute to get it all mixed in

8. 6: Line funnel with coffee filter or cheesecloth and put tube of funnel in test tube • 7. Pour strawberry (or banana) mixture into funnel with coffee filter and let all the liquid drip out into the glass • 8. After liquid has been extracted, dispose of cloth and strawberry (or banana) pulp. THIS COULD TAKE AWHILE (10 min max) • 9. You should have ¼ of the test tube filled with the extract

9. 10. Carefully while tipping the test tube with the strawberry (or banana) liquid, add chilled alcohol slowly by running it down the side until it has formed a thin layer on top of the strawberry (or banana) liquid * Don’t let the liquids mix or get shaken together Almost Done! Ready to see some DNA?!

10. 11. Dip the bamboo skewer into the test tube to reach the layer between the strawberry or banana mixture and the alcohol • 12. When you pull up the skewer you see a white stringy material This is DNA containing strawberry/ banana genes!

11. Conclusions: DNA is far too narrow to see, but if there are thousands of strands grouped together, it can become thick enough to see to the naked eye!

12. Concluding Questions: • 1. Was your hypothesis correct or incorrect? Explain. • 2. How might the DNA of organisms such as humans, monkeys, dogs, etc compare to the strawberry and banana’s DNA? One half of the DNA strand reads: ATACATGGCACT Write the complimentary strand here: _______________

13. The End!