Experiment 2: Measuring Antibiotic Resistance
Question # 00132311
Posted By:
Updated on: 11/10/2015 08:54 AM Due on: 12/10/2015

Experiment 2: Measuring Antibiotic Resistance
In this experiment you will look at the ability of common antibiotics and other antibacterial agents to kill bacteria commonly found in your environment. You will use the
bacterial lawn from the plate that produced the largest quantity of bacteria in the first
lab.
Materials
1 Ampicillin Disc (marked)
10 mL 8.25% Bleach Solution
Forceps
1 Kanamycin Disc (marked)
1 Nutrient agar plate from the
previous lab
1 Penicillin disc (marked)
Permanent Marker
Ruler
Parafilm®
Note: Be sure to wear gloves and use the forceps when handling the discs. Always pick
them up if spilled.
Procedure
1. Using one of the plates covered with bacteria from the first lab, draw four even
quadrants onto the bottom of the plate. Label them penicillin, ampicillin,
kanamycin and control.
2. Wearing your gloves, goggles, and apron, open the plate and place the
appropriate disks into the appropriate quadrants using forceps. Do not place
anything in the control quadrant. DO NOT TOUCH THE PLATE WITHOUT GLOVES.
3. Place the lid back onto the plate and cover it with Parafilm®. Allow it to incubate
in a warm area for 3 days.
4. After 3 days, observe the zone of resistance from each disc (the region
surrounding the disks where no bacteria grew). Using a ruler, measure these
zones from the bottom of the agar plate.
5. After you are done with the experiment, pour enough bleach solution to cover
the surface of the agar. Allow the plate to rest for 10 - 20 minutes. Seal the plate
with Parafilm® and dispose appropriately.
© 2013 eScience Labs, LLC.
All Rights Reserved
Post-Lab Questions
1. Did your bacterial lawn contain only one species of bacteria? If not, why do you
think that is? Can you tell?
2. Which antibiotic was most effective in killing the bacterial lawn? Which was the
least effective?
3. Each bacterial species shows different antibiotic susceptibility. What can you say
about the bacteria that you grew?
© 2013 eScience Labs, LLC.
All Rights Reserved
In this experiment you will look at the ability of common antibiotics and other antibacterial agents to kill bacteria commonly found in your environment. You will use the
bacterial lawn from the plate that produced the largest quantity of bacteria in the first
lab.
Materials
1 Ampicillin Disc (marked)
10 mL 8.25% Bleach Solution
Forceps
1 Kanamycin Disc (marked)
1 Nutrient agar plate from the
previous lab
1 Penicillin disc (marked)
Permanent Marker
Ruler
Parafilm®
Note: Be sure to wear gloves and use the forceps when handling the discs. Always pick
them up if spilled.
Procedure
1. Using one of the plates covered with bacteria from the first lab, draw four even
quadrants onto the bottom of the plate. Label them penicillin, ampicillin,
kanamycin and control.
2. Wearing your gloves, goggles, and apron, open the plate and place the
appropriate disks into the appropriate quadrants using forceps. Do not place
anything in the control quadrant. DO NOT TOUCH THE PLATE WITHOUT GLOVES.
3. Place the lid back onto the plate and cover it with Parafilm®. Allow it to incubate
in a warm area for 3 days.
4. After 3 days, observe the zone of resistance from each disc (the region
surrounding the disks where no bacteria grew). Using a ruler, measure these
zones from the bottom of the agar plate.
5. After you are done with the experiment, pour enough bleach solution to cover
the surface of the agar. Allow the plate to rest for 10 - 20 minutes. Seal the plate
with Parafilm® and dispose appropriately.
© 2013 eScience Labs, LLC.
All Rights Reserved
Post-Lab Questions
1. Did your bacterial lawn contain only one species of bacteria? If not, why do you
think that is? Can you tell?
2. Which antibiotic was most effective in killing the bacterial lawn? Which was the
least effective?
3. Each bacterial species shows different antibiotic susceptibility. What can you say
about the bacteria that you grew?
© 2013 eScience Labs, LLC.
All Rights Reserved

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Rating:
5/
Solution: Experiment 2: Measuring Antibiotic Resistance