From fruit to DNA: Extracting the secrets of life in the kitchen

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DNA is an invisibly thin, very long strand present in every living cell on Earth. It is like a book containing all the instructions to create a living organism using just four different letters. The DNA found in each human cell is almost 2 meters long! If all the DNA in a human adult were laid end to end, the DNA would measure twice the diameter of the solar system! In this experiment, DNA will appear right in front of the children’s eyes as it’s pulled from the pulp of strawberries. Strawberries are well-suited for this activity because they contain 8 copies of every gene, unlike the usual 2 copies in human DNA, and thus provide a large quantity of DNA to extract. Even though DNA is usually invisible to the naked eye, we can observe it directly by clumping together many different strands. The process is simple and uses common household items - we only need dish soap, salt, and rubbing alcohol! The soap helps to break open the cell walls and nuclear membranes, releasing the DNA from the crushed strawberries. Salt helps to stabilize the DNA strands and alcohol causes them to clump together. Shiny white strands of DNA will bubble out of the red strawberry extract into the alcohol layer and can be collected in a small tube to take home! Children will learn about the structure of DNA, basic ideas about genetics, and experimentation in the lab. And they can eat strawberries after!