Question 1

Which of the following antibiotics causes misreading of mRNA?

Accepted Answer

A)   tetracyclines - bind with 30S subunit
B)   aminoglycoside - changes shape of 30S units
C)   chloramphenicol - inhibits peptide bonds at 50S subunit
D)   oxazolidinone - prevents formation of 70S ribosome
E)   streptogamin - prevents release of peptide from 70S ribosomeF) A) and E)
G) C) and D)

Question 2

Figure 20.2  The antibiotic chloramphenicol binds to the 50S subunit of the ribosome, as shown in Figure 20.2. The effect is to

Accepted Answer

A)   prevent peptide bond formation in prokaryotes.
B)   prevent transcription in prokaryotes.
C)   prevent polypeptide elongation in eukaryotes.
D)   prevent ribosome formation in bacteria.
E)   prevent mRNA-ribosome binding in eukaryotes.F) B) and E)
G) All of the above

Question 3

More than half of our antibiotics are

Accepted Answer

A)   synthesized in laboratories.
B)   produced by Fleming.
C)   produced by eukaryotic organisms.
D)   produced by fungi.
E)   produced by bacteria.F) A) and B)
G) None of the above

Question 4

Table 20.2
The following results were obtained from a disk-diffusion test for microbial susceptibility to antibiotics. Staphylococcus aureus was the test organism.
   Antibiotic  Zone of Inhibition A3 mmB7 mmC0 mmD10 mm\begin{array} { | l | l | } \hline { 	ext { Antibiotic } } & 	ext { Zone of Inhibition } \\hline \mathrm { A } & 3 \mathrm {~mm} \\hline \mathrm { B } & 7 \mathrm {~mm} \\hline \mathrm { C } & 0 \mathrm {~mm} \\hline \mathrm { D } & 10 \mathrm {~mm} \\hline\end{array} Antibiotic ABCD​ Zone of Inhibition 3 mm7 mm0 mm10 mm​​ 
-In Table 20.2, the most effective antibiotic tested was

Accepted Answer

A)   A.
B)   B.
C)   C.
D)   D.
E)   The answer cannot be determined based on the information provided. F) B) and E)
G) B) and D)

Question 5

Table 20.1
The following data were obtained from a broth dilution test.
   Concentration of Antibiotic X Growth  Growth in  Subculture 2μg/ml++10μg/ml−+15μg/ml−−25μg/ml−−\begin{array} { | l | l | c | } \hline 	ext { Concentration of Antibiotic } X & 	ext { Growth } & \frac { 	ext { Growth in } } { 	ext { Subculture } } \\hline 2 \mu \mathrm { g } / \mathrm { ml } & + & + \\hline 10 \mu \mathrm { g } / \mathrm { ml } & - & + \\hline 15 \mu \mathrm { g } / \mathrm { ml } & - & - \\hline 25 \mu \mathrm { g } / \mathrm { ml } & - & - \\hline\end{array} Concentration of Antibiotic X2μg/ml10μg/ml15μg/ml25μg/ml​ Growth +−−−​ Subculture  Growth in ​++−−​​ 
-5)  In Table 20.1, as illustrated by the data shown, the minimal bactericidal concentration of antibiotic X is

Accepted Answer

A)   10 ?g/ml.
B)   2 ?g/ml.
C)   25 ?g/ml.
D)   15 ?g/ml.
E)   The answer cannot be determined based on the information provided. F) All of the above
G) A) and B)

Question 6

Which of the following statements about drugs that competitively inhibit DNA polymerase or RNA polymerase is FALSE?

Accepted Answer

A)   They are used against viral infections.
B)   They cause cellular plasmolysis.
C)   They can affect host cell DNA synthesis.
D)   They interfere with protein synthesis.
E)   They can potentially cause mutations.F) A) and D)
G) D) and E)

Question 7

Antimicrobial peptides (AMPs)  frequently work by

Accepted Answer

A)   disrupting the plasma membrane.
B)   hydrolyzing peptidoglycan.
C)   complementary base pairing with DNA.
D)   inhibiting cell-wall synthesis.
E)   inhibiting protein synthesis.F) All of the above
G) B) and D)

Question 8

Niclosamide prevents ATP generation in mitochondria. You would expect this drug to be effective against

Accepted Answer

A)   helminths.
B)   gram-positive bacteria.
C)   Mycobacterium tuberculosis.
D)   viruses.
E)   gram-negative bacteria.F) B) and E)
G) A) and B)

Question 9

The antimicrobial drugs with the broadest spectrum of activity are

Accepted Answer

A)   chloramphenicol.
B)   tetracyclines.
C)   penicillin G.
D)   macrolides.
E)   aminoglycosides.F) None of the above
G) C) and D)

Question 10

Which of the following statements is FALSE?

Accepted Answer

A)   Interferon inhibits glycolysis.
B)   Acyclovir inhibits DNA synthesis.
C)   Azoles inhibit plasma membrane synthesis.
D)   Amantadine inhibits the release of viral nucleic acid.
E)   Fluoroquinolone inhibits DNA synthesis.F) B) and D)
G) C) and D)

Question 11

Both trimethoprim and sulfamethoxazole inhibit reactions along the same metabolic pathway.

Accepted Answer

A) True 
 B)False

Question 12

Which of the following antibiotics is NOT bactericidal?

Accepted Answer

A)   polyenes
B)   cephalosporins
C)   penicillin
D)   aminoglycosides
E)   rifampinsF) All of the above
G) C) and D)

Question 13

To date, most of our natural antibiotics have been found to be produced by members of what genus?

Accepted Answer

A)   Bacillus
B)   Paenibacillus
C)   Streptomyces
D)   Penicillium
E)   CephalosporiumF) A) and D)
G) A) and C)

Question 14

Table 20.1
The following data were obtained from a broth dilution test.
   Concentration of Antibiotic X Growth  Growth in  Subculture 2μg/ml++10μg/ml−+15μg/ml−−25μg/ml−−\begin{array} { | l | l | c | } \hline 	ext { Concentration of Antibiotic } X & 	ext { Growth } & \frac { 	ext { Growth in } } { 	ext { Subculture } } \\hline 2 \mu \mathrm { g } / \mathrm { ml } & + & + \\hline 10 \mu \mathrm { g } / \mathrm { ml } & - & + \\hline 15 \mu \mathrm { g } / \mathrm { ml } & - & - \\hline 25 \mu \mathrm { g } / \mathrm { ml } & - & - \\hline\end{array} Concentration of Antibiotic X2μg/ml10μg/ml15μg/ml25μg/ml​ Growth +−−−​ Subculture  Growth in ​++−−​​ 
-In Table 20.1, the minimal inhibitory concentration of antibiotic X is

Accepted Answer

A)   25 ?g/ml.
B)   15 ?g/ml.
C)   2 ?g/ml.
D)   10 ?g/ml.
E)   The answer cannot be determined based on the information provided. F) B) and D)
G) B) and C)

Question 15

Protozoan and helminthic diseases are difficult to treat because

Accepted Answer

A)   their cells are structurally and functionally similar to human cells.
B)   they replicate inside human cells.
C)   they do not reproduce.
D)   they have more genes than bacteria.
E)   they do not have ribosomes.F) All of the above
G) B) and D)

Exam 20: Antimicrobial Drugs

The antimicrobial drugs with the broadest spectrum of activity are

Correct Answer
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Antimicrobial peptides (AMPs) frequently work by

Correct Answer
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Which of the following antibiotics causes misreading of mRNA?

Correct Answer
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Which of the following statements is FALSE?

Correct Answer
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Niclosamide prevents ATP generation in mitochondria. You would expect this drug to be effective against

Correct Answer
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Correct Answer
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Protozoan and helminthic diseases are difficult to treat because

Correct Answer
verified

Correct Answer
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Correct Answer
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Both trimethoprim and sulfamethoxazole inhibit reactions along the same metabolic pathway.

Correct Answer
verified

More than half of our antibiotics are

Correct Answer
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Which of the following antibiotics is NOT bactericidal?

Correct Answer
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To date, most of our natural antibiotics have been found to be produced by members of what genus?

Correct Answer
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Figure 20.2 The antibiotic chloramphenicol binds to the 50S subunit of the ribosome, as shown in Figure 20.2. The effect is to

Correct Answer
verified

Which of the following statements about drugs that competitively inhibit DNA polymerase or RNA polymerase is FALSE?

Correct Answer
verified

Exam 20: Antimicrobial Drugs

The antimicrobial drugs with the broadest spectrum of activity are

Correct AnswerverifiedShow Answer

Antimicrobial peptides (AMPs) frequently work by

Correct AnswerverifiedShow Answer

Which of the following antibiotics causes misreading of mRNA?

Correct AnswerverifiedShow Answer

Which of the following statements is FALSE?

Correct AnswerverifiedShow Answer

Niclosamide prevents ATP generation in mitochondria. You would expect this drug to be effective against

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Protozoan and helminthic diseases are difficult to treat because

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Both trimethoprim and sulfamethoxazole inhibit reactions along the same metabolic pathway.

Correct AnswerverifiedShow Answer

More than half of our antibiotics are

Correct AnswerverifiedShow Answer

Which of the following antibiotics is NOT bactericidal?

Correct AnswerverifiedShow Answer

To date, most of our natural antibiotics have been found to be produced by members of what genus?

Correct AnswerverifiedShow Answer

Figure 20.2 The antibiotic chloramphenicol binds to the 50S subunit of the ribosome, as shown in Figure 20.2. The effect is to

Correct AnswerverifiedShow Answer

Which of the following statements about drugs that competitively inhibit DNA polymerase or RNA polymerase is FALSE?

Correct AnswerverifiedShow Answer

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