EBK MICROBIOLOGY
12th Edition
ISBN: 8220100659720
Author: CASE
Publisher: PEARSON
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Chapter 20, Problem 4A
The following data were obtained from a disk-diffusion test.
| Antibiotic | Zone of Inhibition |
| A | 15 mm |
| B | 0 mm |
| c | 7 mm |
| D | 15 mm |
- a. Which antibiotic was most effective against the bacteria being tested?
- b. Which antibiotic would you recommend for treating a disease caused by this bacterium?
- c. Was antibiotic A bactericidal or bacteriostatic? How can you tell?
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Students have asked these similar questions
What is the purpose of diluting a culture by making "quadrant streaks" (or "streak plating") bacteria, and what can we use them for? Check all that apply
A.
To observe colony morphology/color
B.
To isolate viral plaques
C.
testing growth conditions or treatments (such as media, antibiotics, incubation temperature etc.,)
D.
To isolate a clonal population of bacteria from the rest of the culture
E.
For subculturing (transferring to new media so we can grow more bacteria, storing the plate in a fridge for repeated use so the bacteria don't die quickly)
F.
Accurate quantification (to calculate CFU/mL)
G.
To know what strain of bacteria you're working with, since you can tell based on how it looks on the plate.
H.
To lower risk of contamination/identify contamination
Based on the following image, which concentration of antibiotic would be considered the minimum bactericidal concentration (MBC)?
a. 8 ug/mlb. 16 ug/mlc. 25 ug/ml
After an antimicrobial drugs test, the following results were obtained from a disk-diffusion test against a bacterium. Antiboitic A= 6mm
Antibiotic B= 18mm
Antibiotic C= 11mm
Antibiotic D= 19mm
which drug should be used to treat an infect caused by this bacterium (assuming everything else is equal about these antibiotics)?
Chapter 20 Solutions
EBK MICROBIOLOGY
Ch. 20 - DRAW IT Show where the following antibiotics work:...Ch. 20 - List and explain five criteria used to identify an...Ch. 20 - What similar problems are encountered with...Ch. 20 - Define drug resistance. How is it produced? What...Ch. 20 - List the advantages of using two chemotherapeutic...Ch. 20 - Why does a cell die from the following...Ch. 20 - How does each of the following inhibit...Ch. 20 - The OH is missing from carbon 39 in ddI. How does...Ch. 20 - Compare the method of action of the following...Ch. 20 - NAME IT This microorganism is not susceptible to...
Ch. 20 - Which of the following pairs is mismatched? a....Ch. 20 - Prob. 2MCQCh. 20 - Prob. 3MCQCh. 20 - An antimicrobial agent should meet all of the...Ch. 20 - The most selective antimicrobial activity would be...Ch. 20 - Prob. 6MCQCh. 20 - Which of the following will not affect eukaryotic...Ch. 20 - Cell membrane damage causes death because a. the...Ch. 20 - A drug that intercalates into DNA has the...Ch. 20 - Chloramphenicol binds to the 50S portion of a...Ch. 20 - Prob. 1ACh. 20 - Why is idoxuridine effective if host cells also...Ch. 20 - Some bacteria become resistant to tetracycline...Ch. 20 - The following data were obtained from a...Ch. 20 - Prob. 5ACh. 20 - The following results were obtained from a broth...Ch. 20 - Vancomycin-resistant Enterococcus faecalis was...Ch. 20 - Prob. 2CAECh. 20 - Prob. 3CAE
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