Streak Plate For Isolated Colonies

1. Stick wire loop in bunsen burner flame until the wire (esp. the loop on the end!) turns red-hot.
2. Let the wire cool for a little bit, then stick it into the bacterial broth
3. Open the petri dish, and on the outside portion of the petri dish, rub the loop back and forth about a dozen times
4. Close the petri dish, rotate it 90 degrees, and stick the loop back into the flame until red hot
5. Let the wire cool, then on the opposite end of the first bacterial streaks toward the top, rub the loop back and forth three times making sure that it crosses the first set of streaks, and then rub back and forth a few more times towards the equator of the petri-dish, making sure not to cross the first set of streaks
6. Clost the petri dish, rotate it 90 degrees, and stick the loop back into the flame until red hot
7. Let the wire cool, then on the opposite end of the second bacterial streaks, rub the loop back and forth three times making sure that it crosses the second set of streaks, and then rub back and forth a few more times towards the first set of streaks making sure not to cross the second or first sets of streaks.
8. Close the petri dish, stick loop back into flame.
9. Put the petri-dish into the incubator

Note: Try not the puncture the agar while rubing the loop across its surface!

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