THIS IS WHAT YOUR DNA LOOKS LIKE

If you’ve ever wanted to check out DNA with your naked eyes, grab some strawberries. The cells in strawberries have eight copies of each chromosome, making it easy to quickly extract a lot of DNA by breaking them open. The red layer at the bottom of this test tube is a mixture of mashed strawberries, water, table salt, and dish detergent. The soapy detergent helps dissolve the membranes of the fruit’s cells, releasing their DNA and other cellular content. The sodium ions from the salt then bind to the negatively charged phosphate groups on the DNA strands. Adding a layer of rubbing alcohol on top of the red mixture causes this DNA-sodium complex, which is not very soluble in the alcohol, to clump up into visible strands at the boundary of the layers.

Submitted by Amy Davis Roth. Do the experiment yourself, and enter our photo contest.

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