BANANA DNA EXTRACTION STATION

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BANANA DNA EXTRACTIONSTATION
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PROCEDURE

• Place two bananas (peeled) and one cup (250mL) of
  distilled water into a blender.
• Blend for 15 to 20 seconds (or until the solution
  is in a slurry)
• Place 25mL of extraction buffer into a beaker.
  Add 2 heaping teaspoons of the banana slurry to
  the beaker.
• Slowly stir banana-buffer mixture for 5-10
  minutes.
• Filter (see filtering apparatus set-up to the
  right) the mixture through cheesecloth into a
  test tube until there is 5mL in the tube.
• Gently add cold 95 ethanol to the strained
  banana mixture.
• Let the solution sit for 2-3 minutes without
  disturbing it. It is important to NOT shake the
  tube.

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ONION DNA EXTRACTIONSTATION
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PROCEDURE

• Cut an inch square out of the center of 3 medium
  onions.
• Chop and place in a blender.
• Add 100 ml of detergent/salt solution.
• Blend on high 30 sec-1 minute.
• Strain the mixture into a beaker using a strainer
  with a coffee filter.
• Add 20-30 ml meat tenderizer and stir to mix
• Place 6 ml filtrate (see filtering apparatus
  set-up to the right) in a test tube.
• Pour 6 ml ice-cold ethanol carefully down the
  side of the tube to form a layer.
• Let the mixture sit undisturbed 2-3 minutes until
  bubbling stops.
• The DNA will float in the alcohol.
• Swirl a glass rod at the interface of the two
  layers to see the small threads of DNA.

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HUMAN CHEEK CELL DNA EXTRACTIONSTATION
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PROCEDURE
This procedure will collect some of the buccal
cells that line the inside of your mouth. These
cells are continuously being sloughed off by your
cheeks.

• Swill two teaspoons (10 ml) 0.9 percent salt
  water in your mouth for 30 seconds.
• This amount of swishing will actually become
  quite laborioushang in there!
• Spit the water into your cup.
• Pour this into a large test tube containing 1
  teaspoon (5 ml) 25 percent liquid detergent.
• Cap tube and gently rock it on its side for 23
  minutes.
• The detergent will break open the cell membrane
  to release the DNA into the soap solution. Do not
  be too vigorous while mixing! DNA is a very long
  molecule. Physical abuse can break it into
  smaller fragments, a process known as shearing.
• Open and slightly tilt the tube and pour 1
  teaspoon (5 ml) fluid ounces of the chilled 95
  percent ethanol down the side of the tube so that
  it forms a layer on the top of your soapy
  solution.
• Allow tube to stand for 1 minute.
• Place a thin acrylic or glass rod into the tube.
• Stir or twirl the rod in one direction to wind
  the DNA strands onto the rod. Be careful to
  minimize mixing of the ethanol and soapy layers.
  If too much shearing has occurred, the DNA
  fragments may be too short to wind up, and they
  may form clumps instead. You can try to scrape
  these out with the rod.