Microbiology: An Introduction (13th Edition)
13th Edition
ISBN: 9780134605180
Author: Gerard J. Tortora, Berdell R. Funke, Christine L. Case, Derek Weber, Warner Bair
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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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)?
The following results were obtained from a disk diffusion test for a strain of Escherichia coli.
Chemotherapeutic
Zone of inhibition (mm)
A
7
B
10
C
18
D
3
Which drug above (A, B, C, or D) is most effective against this E. coli strain?
***Which drug above (A, B, C, or D) is most effective against Staphylococcus aureus? Explain your answer.
Suppose you do the Kirby-Bauer test on a hypothetical Staphylococcus species with penicillin and tetracycline. You record diameters of 20mm for tetracycline and 24mm for penicillin. Which antibiotic is most effective against this bacterium and why? Please explain and interpret these results.
Chapter 20 Solutions
Microbiology: An Introduction (13th Edition)
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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