Question 1

Selective (action/toxicity/treatment) means that a given antimicrobial agent is more toxic to a pathogen than to the host being treated.

Accepted Answer

The answer of Selective (action/toxicity/treatment) means that a given antimicrobial...

Question 2

Which of the following steps in the folic acid synthesis pathway is specifically inhibited by sulfonamides?

Accepted Answer

A)   the conversion of tetrahydrofolic acid to PABA
B)   the conversion of PABA to dihydrofolic acid
C)   the conversion of dihydrofolic acid to tetrahydrofolic acid
D)   the conversion of PABA to tetrahydrofolic acid
E)   the conversion of dihydrofolic acid to PABA

Question 3

Amoxicillin is very effective for treating infections with Gram-positive bacteria but rarely causes side effects in humans. This is an example of

Accepted Answer

A)   selective toxicity.
B)   narrow spectrum of action.
C)   a broad-spectrum antimicrobial.
D)   antibiotic resistance.
E)   altruism.

Question 4

Antisense nucleic acids interfere with protein synthesis.

Accepted Answer

A) True 
 B)False

Question 5

The ratio of a medication's dose that can be tolerated to its effective dose is the therapeutic (MIC/index/range) of the medication.

Accepted Answer

The answer of The ratio of a medication's dose that...

Question 6

Which of the following is a primary advantage of semisynthetic drugs?

Accepted Answer

A)   They are less stable and consequently have fewer side effects.
B)   They work faster.
C)   They are more effective than the unmodified natural antibiotics.
D)   They must be administered intravenously.
E)   They are not readily absorbed.

Question 7

A drug is structurally similar to PABA and inhibits folic acid synthesis. It is most likely a(n)

Accepted Answer

A)   nucleic acid analog.
B)   penicillin.
C)   tetracycline.
D)   azole.
E)   sulfonamide.

Question 8

Most broad-spectrum antibiotics act by

Accepted Answer

A)   inhibiting the synthesis of the cell wall.
B)   inhibiting protein synthesis.
C)   inhibiting nucleic acid synthesis.
D)   inhibiting metabolic pathways.
E)   disrupting the cytoplasmic membrane.

Question 9

A microbe resistant to a variety of different antimicrobials is said to have (cross/drug/multiple) resistance.

Accepted Answer

The answer of A microbe resistant to a variety of...

Question 10

Figure 10.1 represents a Petri plate. The gray area is where bacteria A is growing, the black area is where bacteria B is growing. The white area is a zone where neither organism is growing. What is the best interpretation of what is observed on the plate?

Accepted Answer

A)   Bacteria B is producing an antibiotic that inhibits the growth of bacteria A.
B)   Bacteria A produces a compound that inhibits the growth of bacteria B.
C)   Bacteria A grows faster than bacteria B.
D)   Bacterial colony B has depleted the nutrients in the area around the colony.
E)   No conclusion can be made from this information.

Question 11

The therapeutic range of an antimicrobial is the

Accepted Answer

A)   ratio of the dose a patient can tolerate to the effective dose.
B)   range of microorganisms the antimicrobial effects.
C)   range of concentrations at which the antimicrobial is both effective and non-toxic.
D)   ratio of the concentration of antimicrobial in the blood to the oral dose.
E)   length of time the medication persists in the body after a single dose.

Question 12

Which of the following is NOT a target of drugs that inhibit protein synthesis?

Accepted Answer

A)   the shape of the 30S ribosomal subunit
B)   interference with alanine-alanine bridges
C)   the enzymatic site of the 50S ribosomal subunit
D)   movement of the ribosome from one codon to the next
E)   the tRNA docking site

Question 13

It is inappropriate to prescribe antibacterial agents to treat colds or flu because

Accepted Answer

A)   the microbes involved can develop resistance rapidly.
B)   these diseases are transmitted by endospores, which are difficult to kill.
C)   these diseases exhibit cross resistance.
D)   these diseases are caused by viruses.
E)   these diseases can act synergistically with each other.

Question 14

Which of the following groups of drugs can become incorporated into the bones and teeth of a fetus?

Accepted Answer

A)   beta-lactams
B)   aminoglycosides
C)   quinolones
D)   tetracyclines
E)   sulfonamides

Question 15

There are relatively few antifungal medications available compared to antibacterial drugs.

Accepted Answer

A) True 
 B)False

Question 16

Examine the diffusion susceptibility plate results shown in Figure 10.2. Propose an explanation for the appearance of the zone around the S/10 disk, and discuss the implications for therapeutic use of this antibiotic for the pathogen tested.

Accepted Answer

The ring of colonies within the outermos...

Question 17

The drug metronidazole is effective on both bacteria and some protozoa. It can therefore be described as a ________ drug.

Accepted Answer

A)   narrow spectrum
B)   broad spectrum
C)   full spectrum
D)   general spectrum
E)   specific spectrum

Question 18

Pentamidine is an example of an antimicrobial

Accepted Answer

A)   used to treat bacterial infections.
B)   effective against helminths.
C)   used to treat viral infections.
D)   effective against eukaryotes, especially protozoa.
E)   used to treat both bacterial and fungal infections.

Question 19

An antimicrobial that inhibits bacterial cell wall synthesis will result in which of the following?

Accepted Answer

A)   Bacterial cells become more susceptible to osmotic pressure.
B)   Bacteria cannot attach to their hosts.
C)   Cytoplasmic membrane proteins lose their function.
D)   The sterols in the bacterial cell wall become nonfunctional.
E)   No change in bacterial cell activity.

Question 20

Which of the following statements is true of selective toxicity?

Accepted Answer

A)   Selective toxicity takes advantage of structural similarities between host and pathogen.
B)   To be effective, an antimicrobial agent must be more toxic to the patient than the pathogen.
C)   Selective toxicity takes advantage of differences in metabolic rates of the host and pathogen.
D)   Selective toxicity damages only pathogenic bacteria and not beneficial bacteria.
E)   Selective toxicity takes advantage of structural and/or metabolic differences between host and pathogen.

Exam 10:Controlling Microbial Growth in the Body: Antimicrobial Drugs

Which of the following is a primary advantage of semisynthetic drugs?

Correct AnswerverifiedShow Answer

A microbe resistant to a variety of different antimicrobials is said to have (cross/drug/multiple) resistance.

Correct AnswerverifiedShow Answer

There are relatively few antifungal medications available compared to antibacterial drugs.

Correct AnswerverifiedShow Answer

Antisense nucleic acids interfere with protein synthesis.

Correct AnswerverifiedShow Answer

Selective (action/toxicity/treatment) means that a given antimicrobial agent is more toxic to a pathogen than to the host being treated.

Correct AnswerverifiedShow Answer

Figure 10.1 represents a Petri plate. The gray area is where bacteria A is growing, the black area is where bacteria B is growing. The white area is a zone where neither organism is growing. What is the best interpretation of what is observed on the plate?

Correct AnswerverifiedShow Answer

The ratio of a medication's dose that can be tolerated to its effective dose is the therapeutic (MIC/index/range) of the medication.

Correct AnswerverifiedShow Answer

An antimicrobial that inhibits bacterial cell wall synthesis will result in which of the following?

Correct AnswerverifiedShow Answer

Pentamidine is an example of an antimicrobial

Correct AnswerverifiedShow Answer

The therapeutic range of an antimicrobial is the

Correct AnswerverifiedShow Answer

It is inappropriate to prescribe antibacterial agents to treat colds or flu because

Correct AnswerverifiedShow Answer

Which of the following groups of drugs can become incorporated into the bones and teeth of a fetus?

Correct AnswerverifiedShow Answer

Examine the diffusion susceptibility plate results shown in Figure 10.2. Propose an explanation for the appearance of the zone around the S/10 disk, and discuss the implications for therapeutic use of this antibiotic for the pathogen tested.

Correct AnswerverifiedThe ring of colonies within the outermos...View AnswerShow Answer

Which of the following is NOT a target of drugs that inhibit protein synthesis?

Correct AnswerverifiedShow Answer

Most broad-spectrum antibiotics act by

Correct AnswerverifiedShow Answer

Which of the following statements is true of selective toxicity?

Correct AnswerverifiedShow Answer

Which of the following steps in the folic acid synthesis pathway is specifically inhibited by sulfonamides?

Correct AnswerverifiedShow Answer

Amoxicillin is very effective for treating infections with Gram-positive bacteria but rarely causes side effects in humans. This is an example of

Correct AnswerverifiedShow Answer

The drug metronidazole is effective on both bacteria and some protozoa. It can therefore be described as a ________ drug.

Correct AnswerverifiedShow Answer

A drug is structurally similar to PABA and inhibits folic acid synthesis. It is most likely a(n)

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
The ring of colonies within the outermos...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified