1. 1. Extracting DNA fromfruitsExtracting DNA fromfruits
2. 2. Verify to have all the materials before starting the experiment (pic. 1). Melt the salt (about 10 g) in 100 ml of water (pic. 2). Add a teaspoon (about 10 g) of liquid soap (pic. 3 and 4).
3. 3. Stir slowly, without making foam, which may hinder the contact between the solution and the banana (pic. 5 and 6). Mash 100g of banana (pic. 7 and 8).
4. 4. Pour the mush into the solution (pic. 9). Wait for 20 minutes.
5. 5. What isWhat is DDNNAA??
6. 6. DNA or desoxyribonucleic acid is a molecule content in the cell nucleus.
7. 7. If we could look DNA closely, we would discover that this molecule is composed by two strands which, joined together, fold up forming a double-helix similar to a spiral stairs. If we could look DNA closely, we would discover that this molecule is composed by two strands which, joined together, fold up forming a double-helix similar to a spiral stairs.
8. 8. The rungs of this stair correspond to chemical substances called nucleobases which form a chemical bond two by two. DNA can be compared to an important instruction book which contains genetic informationuseful for cells to makedifferents chemicals molecules known as proteins.
9. 9. WHO DISCOVERED DNA?WHO DISCOVERED DNA? In 1953, the scientists J. Watson and F. Crick discovered the double-helix structure of DNA. They were helped by the
10. 10. Unfortunately, Franklin did not recived Nobel Price for medicine in 1962 with her collegues Watson and Crick because she died before the assignment of the Prize, but it is necessary to
11. 11. COME BACK TO OURCOME BACK TO OUR EXPERIMENT!!!EXPERIMENT!!!
12. 12. After 20 minutes, filter the mixture (pic. 10-12).
13. 13. Wait until the mixture goes through the filter (pic.13 and 14). Take a sample of 5 ml from the filtered mixture with a syringe (pic. 15 and 16).
14. 14. Move the liquid into the test tube, avoiding making foam (pic. 17). Add 2 ml of pineapple juice using another syringe (pic. 18). Turn upside down the tube 2 or 3 times to facilitate the mixing of the liquids (pic. 19).
15. 15. Add 10 ml of ethyl alcohol (pic. 20 e 21). Wait a few minutes and the ball of DNA will emerge and, using a magnifying glass you'll be able to see it. (fig. 22-24).