E e 13 quickly pipet 8 drops of the broth to the

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E E 13. Quickly pipet 8 drops of the broth to the center of the agar plate. Figure 8. Figure 8. Adding 8 drops of broth to the center of an agar plate. E E 14. Place the pipet in a bucket of bleach. E E 15. Remove the L-shaped spreader from its packaging making sure to only touch the long straight end. E E 16. Spread the broth evenly across the agar so that the entire plate is coated with an even layer of broth. See Figure 9.
Figure 9. Using a L-shaped spreader to coat the surface of an agar plate with broth. E E 17. Replace the lid on the agar plate. E E 18. Place the L-shaped spreader in a bucket of bleach. E E 19. Sterilize the lip of the culture vial by holding above the candle flame. Replace the lid and return the vial to the refrigerator for use in future experiments. E E 20. Extinguish the candle. E E 21. Allow the agar plate to remain undisturbed, lid-side up approximately 1-2 hours until the broth is absorbed by the agar. E E 22. Once the broth has been absorbed into the agar, remove the plastic tweezers from the alcohol and shake to dry. E E 23. Using the sterile tweezers, remove the penicillin disk from its plastic bag. E E 24. Open the lid of the agar plate and quickly transfer the disk to the "Pnc" section of the agar plate. See Figure 10. Figure 10. Using tweezers to place an antibiotic disk onto the center of a labeled agar section. E E 25. Gently press the disk onto the agar surface with the tweezers to ensure proper contact.
E E 26. Return the lid to the agar plate. E E 27. Place the tweezers in the cup of alcohol for 30 seconds, then remove and shake to dry. E E 28. Repeat steps 23-27 for the 2 remaining antibiotic disks. E E 29. Allow the agar plate to remain lid-side up for 10 minutes so that the disks attach securely to the agar surface. E E 30. Place the plate agar-side up in your incubation location and incubate for 12 hours. E E 31. Wipe down your work area with a 10% bleach solution. E E 32. Wash and return items to the kit for future use. E E 33. Wash your hands thoroughly. E E 34. Based on your knowledge of S. epidermidis and the antibiotics used for this experiment, state a hypothesis regarding the resistance of S. epidermidis to each of the drugs. For example: “ S. epidermidis will exhibit resistance to penicillin and will be inhibited by novobiocin and gentamicin.” E E 35. Record your hypothesis in Panel 1 . Part 2: Collecting Data from the Kirby-Bauer Diffusion Test After 12 hours, check the Kirby-Bauer diffusion plate for bacterial growth which should appear as a white film or "lawn" covering the agar. If no growth is observed, continue to incubate for another 12 hours. E E

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