strawberry

In  Mrs. Simmonds seventh grade science class we did a lab on extracting DNA from a strawberry. While yes that may sound crazy and not possible, we were able to get DNA from the strawberry.  

To begin, DNA stands for deoxyribonucleic acid. The strawberries DNA is found in the nucleus of the eukaryotic cells.  DNA is also a double-helical molecule and they are passed on from generation to generation.  DNA extraction is the removal of the DNA from a cell in an organism. Plants have a barrier called the cell wall. It surrounds the cell membrane. A cell membrane protects and also contains its contents. The cell walls also give the plants strength. 

Continuing on, all you need for the lab is ten mL of DNA extraction buffer (dish detergent, water, and salt), five mL of cold ninety-five percent ethanol, a resealable plastic bag, a strawberry, a fifty mL tube, a fifteen mL tube, a piece of cheesecloth, a funnel, two transfer pipettes, and a wooden stick.

  To complete this lab, first take the green leafy part of the strawberry off. Second place the strawberry in a resealable plastic bag and close it carefully removing all of the air in the bag. Third, you want to mash the strawberry gently with your hands for two minutes without breaking the bag. Fourth,  pour the extraction buffer into the bag and mash for one more minute. Fifth, place a funnel into the fifty mL tube and fold the cheesecloth in half and place it into the funnel. Make sure you only fold it in half once. Sixth, you pour it into the funnel with the cheesecloth so the strawberry mixture gets filtered. Then, take one of the pipettes and take two mL of the filtered strawberry mixture and place it into the fifteen mL tube. Lastly, hold the fifteen mL tube at an angle and take the other pipette to use it to transfer the ethanol into the filtered out strawberry mixture. Once the ethanol is added the strawberry mixture and ethanol should go up to seven mL in the tube. You should now have two distinct layers. Make sure you do not mix the mixture with ethanol.

Now for the fun hyper-interactive part of this experiment. Watch as translucent strands of DNA begin to form and clump together. Tiny bubbles in the ethanol may appear. Take the wooden stick and slowly swirl it in the ethanol. Do not touch the strawberry with the stick. Gently remove the stick from the tube and notice the little translucent strands which are strawberry DNA.

In conclusion, this experiment is fun for the ages ten and up with supervision. The good thing about this experiment is that it requires minimum preparations. It is safe to say that this experiment is enjoyed by all ages.

Authors:

Jamie Garcia and Karlie Narcisse