MCB 2004 FINAL EXAM QUESTIONS WITH VERIFIED
ANSWERS
Which of the following methods of action would be bacteriostatic? - Answers - inhibition
of protein synthesis
In the presence of penicillin, a cell dies because - Answers - it undergoes lysis
The antibiotic tetracycline binds to the 30S subunit of the ribosome, as shown by the
dark black bar on the right portion of the diagram in the figure. The effect is to - Answers
- interfere with the attachment of the tRNA to the mRNA-ribosome complex
Which of the following antibiotics is recommended for use against gram-negative
bacteria? - Answers - polymyxin
Which of the following antimicrobial agents is recommended for use against fungal
infections? - Answers - amphotericin B
Niclosamide prevents ATP generation in mitochondria. You would expect this drug to be
effective against - Answers - helminths
More than half of our antibiotics are - Answers - produced by bacteria
To date, most of our natural antibiotics have been found to be produced by members of
what genus? - Answers - Streptomyces
Only microbes produce antimicrobial peptides. - Answers - false
Most of the available antimicrobial agents are effective against - Answers - bacteria
The antimicrobial drugs with the broadest spectrum of activity are - Answers -
tetracyclines
Why is it more difficult to treat viral infections than it is to treat bacterial infections? -
Answers - Viruses use the host cell's processes to carry out their own reproduction
The antibiotic actinomycin D binds between adjacent G-C pairs, thus interfering with -
Answers - transcription
More than half of the antibiotics used today are produced by __________. - Answers -
streptomyces species
Sulfanilamides interfere with __________. - Answers - folic acid synthesis in bacteria
, PABA serves as the competitive inhibitor in the action of sulfanilamides. - Answers -
false
In what way are semisynthetic penicillins and natural penicillins alike? - Answers - Both
are based on B-lactam
The antibiotic chloramphenicol binds to the 50S subunit of the ribosome, as shown in
the figure. The effect is to - Answers - prevent peptide bond formation in prokaryotes
Which of the following antimicrobial agents has the fewest side effects? - Answers -
Penicillin
Which of the following antibiotics does NOT interfere with cell wall synthesis? - Answers
- macrolides
Amantadine inhibits the release of viral nucleic acid - Answers - true
Flurorquinolone inhibits DNA sythesis - Answers - true
Acyclovir inhibits DNA sythesis - Answers - true
Azoles inhibit plasma membrane synthesis - Answers - true
Which of the following organisms would MOST likely be sensitive to natural penicillin? -
Answers - Streptococcus pyogenes
Which of the following would be selective against the tubercle bacillus? - Answers -
ethambutol inhibits mycolic acid synthesis
The structures of the influenza drug Tamiflu and sialic acid, the substrate for influenza
virus's neuramidase, are shown in the figure. What is the method of action of Tamiflu? -
Answers - competitive inhibition
Which of the following affects eukaryotic cells? - Answers - antiprotozoal drugs
antihelminthic drugs
nucleotide analogs
antifungal drugs
If penicillin G is chosen as the best treatment for a given infection, what microorganisms
are most likely the cause? - Answers - gram-positive bacteria
Due to its target, rifamycins can be effective over a broad spectrum. - Answers - true
Antiviral drugs target viral processes that occur during viral infection. - Answers - true
ANSWERS
Which of the following methods of action would be bacteriostatic? - Answers - inhibition
of protein synthesis
In the presence of penicillin, a cell dies because - Answers - it undergoes lysis
The antibiotic tetracycline binds to the 30S subunit of the ribosome, as shown by the
dark black bar on the right portion of the diagram in the figure. The effect is to - Answers
- interfere with the attachment of the tRNA to the mRNA-ribosome complex
Which of the following antibiotics is recommended for use against gram-negative
bacteria? - Answers - polymyxin
Which of the following antimicrobial agents is recommended for use against fungal
infections? - Answers - amphotericin B
Niclosamide prevents ATP generation in mitochondria. You would expect this drug to be
effective against - Answers - helminths
More than half of our antibiotics are - Answers - produced by bacteria
To date, most of our natural antibiotics have been found to be produced by members of
what genus? - Answers - Streptomyces
Only microbes produce antimicrobial peptides. - Answers - false
Most of the available antimicrobial agents are effective against - Answers - bacteria
The antimicrobial drugs with the broadest spectrum of activity are - Answers -
tetracyclines
Why is it more difficult to treat viral infections than it is to treat bacterial infections? -
Answers - Viruses use the host cell's processes to carry out their own reproduction
The antibiotic actinomycin D binds between adjacent G-C pairs, thus interfering with -
Answers - transcription
More than half of the antibiotics used today are produced by __________. - Answers -
streptomyces species
Sulfanilamides interfere with __________. - Answers - folic acid synthesis in bacteria
, PABA serves as the competitive inhibitor in the action of sulfanilamides. - Answers -
false
In what way are semisynthetic penicillins and natural penicillins alike? - Answers - Both
are based on B-lactam
The antibiotic chloramphenicol binds to the 50S subunit of the ribosome, as shown in
the figure. The effect is to - Answers - prevent peptide bond formation in prokaryotes
Which of the following antimicrobial agents has the fewest side effects? - Answers -
Penicillin
Which of the following antibiotics does NOT interfere with cell wall synthesis? - Answers
- macrolides
Amantadine inhibits the release of viral nucleic acid - Answers - true
Flurorquinolone inhibits DNA sythesis - Answers - true
Acyclovir inhibits DNA sythesis - Answers - true
Azoles inhibit plasma membrane synthesis - Answers - true
Which of the following organisms would MOST likely be sensitive to natural penicillin? -
Answers - Streptococcus pyogenes
Which of the following would be selective against the tubercle bacillus? - Answers -
ethambutol inhibits mycolic acid synthesis
The structures of the influenza drug Tamiflu and sialic acid, the substrate for influenza
virus's neuramidase, are shown in the figure. What is the method of action of Tamiflu? -
Answers - competitive inhibition
Which of the following affects eukaryotic cells? - Answers - antiprotozoal drugs
antihelminthic drugs
nucleotide analogs
antifungal drugs
If penicillin G is chosen as the best treatment for a given infection, what microorganisms
are most likely the cause? - Answers - gram-positive bacteria
Due to its target, rifamycins can be effective over a broad spectrum. - Answers - true
Antiviral drugs target viral processes that occur during viral infection. - Answers - true
