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

Question 1

Semisynthetic drugs represent all of the following improvements EXCEPT:

A) they work faster.
B) they are broader spectrum in their action.
C) they are more stable in the stomach.
D) they are less susceptible to deactivation by bacterial enzymes.
E) they are more readily absorbed in the intestines.

Answer 1

A

Question 2

Which of the following is a class of drugs that inhibits the formation of fungal cell walls?

A) allylamines
B) aminoglycosides
C) beta- lactams
D) echinocandins
E) monobactams

Answer 2

D

Question 3

Which of the following works by inhibiting ergosterol synthesis?

A) terbinafine
B) fluconazole
C) amphotericin B
D) Both A and B are correct.
E) A, B, and C are correct.

Answer 3

D

Question 4

All of the following drugs affect the proper function of the ribosome EXCEPT:

A) streptomycin.
B) erythromycin.
C) tetracyclines.
D) polymyxin.
E) chloramphenicol.

Question 5

Which of the following is NOT caused by the disruption of normal microbiota as a result of antimicrobial drug therapy?

A) thrush
B) pseudomembranous colitis
C) anaphylactic shock
D) vaginitis
E) All of these are caused by the disruption of normal microbiota.

Question 6

The cell wall inhibiting drug bacitracin works by

A) blocking the transport of cell wall molecules from the cytoplasm.
B) preventing the formation of alanine- alanine bridges.
C) inhibiting the enzyme that synthesizes glucan.
D) disrupting the formation of the mycolic acid layer of the cell wall.
E) preventing the cross- linkage of NAM subunits.

Question 7

All of the following statements concerning development of antibiotic resistance are true EXCEPT:

A) resistant cells are normally in the minority in a bacterial population.
B) it is often mediated by R- plasmids.
C) new resistance genes can be gained through transformation, transduction, or conjugation.
D) resistance can occur through mutation of existing bacterial genes.
E) resistant cells grow more efficiently and quickly than susceptible cells.

Question 8

The scientist who coined the term "antibiotic" was

A) Kirby.
B) Ehrlich.
C) Bauer.
D) Fleming.
E) Domagk.

Question 9

Which of the following is NOT true of the inhibition observed in a Kirby- Bauer test?

A) It is a result of diffusion of the drug out of the paper disk.
B) It is measured as a diameter.
C) It is a clearing zone with no growth.
D) The larger the zone, the more resistant the organism is.
E) It is measured after incubation.

Question 10

Which of the following types of antimicrobial drugs make microbes more susceptible to osmotic pressure?

A) drugs that inhibit metabolic pathways
B) drugs that inhibit nucleic acid synthesis
C) drugs that inhibit protein synthesis
D) drugs that inhibit cell wall synthesis
E) drugs that block a pathogen's recognition of its host

Question 11

Which of the following inhibitors of protein synthesis is used to treat viral infections?

A) fomiversen
B) mupirocin
C) streptogramin
D) gentamicin
E) chloramphenicol

Question 12

The type of antimicrobial drug that would be least toxic to humans is a drug that

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

Question 13

All of the following are targets of drugs that inhibit protein synthesis EXCEPT:

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

Question 14

Beta- lactamase production is an example of which of the following types of resistance?

A) inactivation of the drug
B) change in the permeability of the drug
C) overproduction of an enzyme in a key metabolic pathway
D) removal of the drug via a pump
E) alternation of the target

Question 15

Sulfonamides

A) indirectly inhibit the synthesis of nucleic acids.
B) are antimetabolic drugs.
C) were the first widely used antimicrobial drugs.
D) Both A and B are correct.
E) A, B, and C are correct.

Question 16

Another term for the Kirby- Bauer test is the

A) minimum bactericidal concentration test.
B) broth dilution test.
C) Etest.
D) minimum inhibitory concentration test.
E) diffusion susceptibility test.

Question 17

All of the following are antibiotic- producing genera of microbes EXCEPT:

A) Mycobacterium
B) Cephalosporium
C) Bacillus
D) Penicillium
E) Streptomyces

Question 18

Probiotics

A) involve microbial antagonism.
B) are an alternative to the use of chemotherapy.
C) include the use of Lactobacillus to relieve diarrhea in children.
D) Both A and B are correct.
E) A, B, and C are correct.

Question 19

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

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

Question 20

Beta- lactam antibiotics have an effect on which of the following types of cells?

A) bacterial cells
B) animal cells
C) fungal cells
D) Both B and C are correct.
E) Both A and B are correct.

Question 21

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

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

Question 22

Sulfonamides are structural analogs of

A) MIC.
B) THF.
C) MRSA.
D) PABA.
E) MDR- TB.

Question 23

Which of the following is an incorrect pairing?

A) sulfanilamide; first antibiotic to be discovered
B) Fleming; discovery of penicillin
C) Ehrlich; proposal of the term "chemotherapy"
D) Domagk; discovery of sulfanilamide
E) None of these is an incorrect pairing.

Question 24

The cooperative activity of drugs such as beta- lactam antibiotics and clavulanic acid, a beta- lactamase inhibitor, is known as

A) antimetabolism.
B) chemotherapy.
C) synergism.
D) cross resistance.
E) selective toxicity.

Question 25

All of the following are criteria by which all antimicrobial agents can be evaluated EXCEPT:

A) their efficacy.
B) their route of administration.
C) their spectrum of action.
D) their activity against cell walls.
E) their safety.

Question 26

All antimicrobials are chemotherapeutic agents, but not all chemotherapeutic agents are antimicrobials.

Question 27

Which of the following drugs inhibits nucleic acid synthesis specifically in prokaryotes?

A) rifampin
B) actinomycin
C) quinolones
D) Both A and B are correct.
E) A, B, and C are correct.

Question 28

Which of the following is a measurement associated with the broth dilution test?

A) cell lysis
B) lack of turbidity
C) the zone of inhibition
D) Both A and B are correct.
E) A, B, and C are correct.

Question 29

Many antimicrobial drugs that affect the cell membrane are used only externally because they can be toxic to humans.

Question 30

The Etest determines which of the following?

A) susceptibility
B) MBC
C) MIC
D) Both A and C are correct.
E) Both B and C are correct.

Question 31

Which of the following is(are) true of selective toxicity?

A) It takes advantage of metabolic differences between host and pathogen.
B) To be effective, an antimicrobial agent must be more toxic to the patient than the pathogen.
C) It takes advantage of structural differences between host and pathogen.
D) Both A and B are correct.
E) Both A and C are correct.

Question 32

An infection of which of the following organs would be the hardest to treat with antimicrobial drugs?

A) colon
B) brain
C) liver
D) kidneys
E) heart

Question 33

Disruption of the normal microbiota can result in infections caused by which of the following microbes?

A) Mycobacterium
B) Candida albicans
C) Clostridium difficile
D) Both A and C are correct.
E) Both B and C are correct.

Question 34

Which of the following types of drugs interferes with events at the end of the HIV replication cycle?

A) protease inhibitors
B) DNA gyrase inhibitors
C) attachment antagonists
D) reverse transcriptase inhibitors
E) nucleotide analogs

Question 35

All of the following are examples of beta- lactam drugs EXCEPT:

A) monobactams.
B) cephalothin.
C) vancomycin.
D) penicillin G.
E) methicillin.

Question 36

Alterations in the structure of which of the following are an important aspect of Gram- negative bacterial resistance to antimicrobial drugs?

A) mitochondria
B) plasmids
C) ribosomes
D) cell membrane
E) porins

Question 37

All of the following are possible consequences of inappropriate antibiotic therapy EXCEPT:

A) killing of the normal microbiota.
B) increased antibiotic resistance.
C) increased microbial antagonism.
D) increased incidence of superinfections.
E) creation of superbugs.

Question 38

Beta- lactam drugs act by inhibiting formation of the cell membrane.

Question 39

Antimicrobial agents that inhibit protein synthesis can be harmful to humans because of the nature of the eukaryotic mitochondrion.

Question 40

Antisense nucleic acids are designed to have no side effects against humans.

Question 41

Drugs that inhibit nucleic acid synthesis include quinolones, rifampin, and actinomycin.

Question 42

AIDS patients are routinely treated with combinations of various anti- HIV drugs; these combinations are called drug .

Question 43

Antimicrobial agents that mimic the chemical structure of DNA building blocks are called .

Question 44

Internal infections can be treated by drugs that are administered orally, intravenously, or .

Question 45

Organs that are commonly affected by drug toxicity include the heart and the liver.

Question 46

Any drug that acts against a disease is called a(n) _ agent.

Question 47

Because they kill many different types of microbes, broad- spectrum antibiotics are more desirable than narrow- spectrum drugs.

Question 48

Brain and spinal cord infections are difficult to treat because most antimicrobial drugs cannot diffuse out of the blood into these organs.

Question 49

Superinfections are serious secondary infections that result from killing the _ _.

Question 50

means that a given antimicrobial agent is more toxic to a pathogen than to the host being treated.

Question 51

The abbreviation stands for the smallest amount of a drug that kills a pathogen.

Question 52

A(n) concentration of a drug is one at which microbes survive, but are not able to grow and reproduce.

Question 53

Competition between beneficial microbes and potential pathogens is called .

Question 54

Praziquantel alters the cell membrane permeability of .

Question 55

A(n) drug is effective against only a few kinds of pathogens.

Question 56

Some bacteria develop resistance to groups of drugs because the drugs are all structurally similar to each other; this is a phenomenon known as .

Question 57

External infections can be treated by administration, in which a drug is applied directly to the site of infection.

Question 58

drugs are semisynthetic drugs developed to combat resistance against an existing drug.

Question 59

If a subculture of an MIC test grows in an MBC test, the concentration of the drug was bactericidal.

Question 60

Sulfonamides are an example of a type of antimicrobial drug known as a(n) _ , because they inhibit certain chemical reactions within bacterial cells.

Question 61

Explain how sulfonamides kill a bacterial cell.

Question 62

Explain the concept of selective toxicity.

Question 63

Why can microbial resistance to antibiotics and other drugs be considered a primarily genetic phenomenon?

Question 64

Discuss the cellular factors that might make a drug more narrow spectrum rather than broad spectrum.

Question 65

Explain why many antibiotics are effective only against cells that are actively growing and reproducing.