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← Summer Solo-Science

Week 5Releases July 20

See strawberry DNA

Mash a strawberry with soapy salt water and lift out a cloudy clump you can actually see — its DNA.

For you to do

You'll break open millions of strawberry cells, then use cold alcohol to make their DNA clump together into a stringy, cloudy blob you can lift with a toothpick.

Grown-up help

A grown-up should get out and pour the rubbing alcohol and stay nearby — it's not for drinking and shouldn't go near eyes. You do the mashing and filtering.

Extract it

Grown-up handles the alcohol

Rubbing alcohol is only for this step and only with an adult. Keep it away from your face and wash hands after.

  1. Put the strawberry in the zip bag and mash it with your hands for a minute.
  2. Add two spoons of soapy salt water (a squirt of dish soap + a pinch of salt in half a cup of water). Mash gently again.
  3. Pour through a coffee filter into a clear cup.
  4. Tilt the cup and slowly pour cold rubbing alcohol down the side so it floats on top. Watch the cloudy layer where they meet.

What's happening

Soap breaks open the **cell** walls and the salt helps the **DNA** clump together. DNA doesn't dissolve in alcohol, so it appears as a white, stringy cloud at the boundary. That clump is the instruction manual that built the whole strawberry. Note what it looks like — careful **observation** is the whole point.