The document provides instructions for isolating DNA from a banana. First, salt is added to help the DNA stay together during processing. Then detergent is used to break down cell membranes. The banana mixture is filtered to remove unwanted materials. Proteins are then digested using a meat tenderizer. Finally, iced rubbing alcohol is added to precipitate the DNA, which can then be removed from the solution using a toothpick. The process allows students to visualize DNA from a common fruit.

1. Isolating DNA from a
banana…yes a banana!!!

3. How do we take out the DNA?
1. a) Salt
Helps DNA keep together during the
process.

4. How do we take out the DNA?
1. b) Detergent (shampoo)
Breaks down the cell membrane
and nuclear membrane.
(NO BUBBLES!!)

5. Filter
2. Filter the banana “goo” with a coffee filter.
-This removes everything that you do not
need.
-Take the filtrate.
Banana goo
What you need!!!

6. "Clean" the DNA
Use a meat tenderizer to digest any proteins
associated with the DNA.

7. Now we remove the DNA
- Add iced rubbing alcohol.
- This will allow the DNA to
precipitate.
- Now you may remove the
DNA with a toothpick.

8. Instructions and Measurements
Materials: (per group)
• piece fruit (~1/4 of a banana)
• 1 coffee filter
• two cups (or beakers ~100 mL)
• 15 ml of iced alcohol
• ~1.5 g (1-2 mL) table salt (NaCl)
• 10 mL water
• 30 mL liquid soap
• 1 toothpick