2020(S11) Lecture:week 1

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Week 1 Tuesday


After a short introduction to the who/what/why for this class, we'll start handling the programming material that's at our fingertips...in our fingertips, even! As you work through this DNA isolation protocol below, be mindful of your questions and your own reactions to this activity. Is this the first time you've ever handled a lump of DNA? How hard is it to isolate DNA, both technically speaking and in terms of the needed equipment? What surprised you? What did you learn and what questions do you still have? What could you do next with this material you've isolated?

DNA from a Strawberry

  1. Pair up and pick up a ziplock baggie with a strawberry in it. IF YOU ARE ALLERGIC TO STRAWBERRIES, please don't do this part.
  2. Push the air out of the baggie as best you can and reseal it.
  3. Being careful not to break the baggie, mash the strawberry with your fingers for ~2 minutes.
  4. Using a medicine cup to measure it, add 10 ml of extraction buffer to the baggie. Extraction buffer is a mixture of 20 ml dish soap, 1.5 tsp of table salt, a sprinkle of meat tenderizer, and 380 ml of spring water.
  5. Mash the strawberry for one minute more.
  6. Place a funnel over a 3oz. bathroom cup.
  7. Fold a piece of cheesecloth into a ~4 inch square and place it in the funnel.
  8. Pour the strawberry mush into the funnel and allow gravity to do its work. You'll throw away the strawberry mush and cheesecloth into the trash, and return the funnel to the kit.
  9. Carefully pour 2 ml of the filtered strawberry juice into a clean, conical tube, using the markings on the side of the tube to know how much to transfer.
  10. Hold the tube at an angle and, using an eye-dropper, carefully DRIBBLE a 5 ml layer of cold 95% Ethanol or 70% isopropanol (your choice) onto the strawberry goop. DO NOT MIX the layers.
  11. Now watch...after a few minutes you should start to see some bubbles, then some white stringy stuff, which is the DNA.
  12. There will be coffee stirrers to remove the DNA from the tube if you'd like to do that. The DNA is best removed by "spooling"--i.e. winding the DNA around the stick with a gentle twirl of stick.
Why are we doing this??

Let's return to the questions from the start of the day:

  • Was this the first time you've ever handled a lump of DNA?
    • Is it what you thought it would look like?
    • Is there more or less than you thought there'd be?
  • How do you know it's DNA?
  • How hard was it to isolate DNA,
    • technically speaking?
    • needed equipment?
  • What surprised you?
  • What did you learn and what questions do you now have?
    • Where did you finally put the DNA you isolated?
    • What did you do with it after you isolated it?
    • Is it OK to just throw it away?

Week 1 Studio


Week 1 Thursday

==Why are we doing this?==