Student Organizer #1
Procedure for Growing Bacterial Colonies

  1. Get from your teacher a pre-poured agar plate with two compartments.
  2. With your marking pen, mark on the bottom the "control" side and the "experimental" side. The control side will not be swabbed. The experimental side will get swabbed.
  3. Get from your teacher one or two cotton swabs. Dampen both sides with tap water. This will make it easier for any collected bacteria to adhere to it.
  4. When you get to your assigned sampling location, rub one end of one of the moistened cotton swabs across the surface you'd like to study. Roll the swab in your fingers as you're rubbing it across the surface to get as large a sample as you can.
  5. When you return to the classroom, lift the edge of the Petri dish on the experimental side just high enough so you can get the cotton swab to make contact with the agar on the experimental side.
  6. Gently rub the end of the cotton swab with your sample across the surface of the agar. Use an 's' pattern being careful not to rub so hard that the agar tears.
  7. Rotate the dish 90 degrees, and apply another "s" pattern perpendicular to the first one.
  8. Replace the cover and seal the dish with masking tape.
  9. On the bottom of the dish print the name of the location tested and the initials of the group members with the marking pen.
  10. Give your sealed dish to your teacher so it can be put into the incubator.
  11. Put the used cotton swab in the bleach solution.
  12. Wash your hands well with soap and water.
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