Microbiology Chapter 14 (OpenStax)

The bacterium known for causing pseudomembranous colitis, a potentially deadly superinfection, is ________.

Clostridium diffcile

The method that can determine the MICs of multiple antimicrobial drugs against a microbial stain using a single agar plate is called the ________.

Etest

Beta-Lactamases can degrade vancomycin.

False

T/F Narrow-spectrum antimicrobials are commonly used for prophylaxis following surgery.

False

Which of the following techniques cannot be used to determine the minimum inhibitory concentration of an antimicrobial drug against a particular microbe?

Kirby-Bauer disk diffusion test

Which of the following combinations would most likely contribute to the development of a superinfection? a. long-term use of narrow-spectrum antimicrobials b. long-term use of broad-spectrum antimicrobials c. short-term use of narrow-spectrum antimicrobials d. short-term use of broad-spectrum antimicrobials

Long term use of a broad-spectrum antimicrobial

Which of the following types of drug-resistance bacteria do not typically persist in individuals as a member of their intestinal microbiota? a. MRSA b. VRE c. CRE d. ESBL-producing bacteria

MRSA

Which of the following antimicrobial drugs is synthetic? a. sulfanilamide b. penicillin c. actinomycin d. neomycin

Sulfanilamide

Echinocandins, known as "penicillin for fungi," target β(1→3) glucan in fungal cell walls.

True

The group of soil bacteria known for their ability to produce a wide variety of antimicrobials is called the ___________.

actinomycetes

Which of the following is an antimalarial drug that is thought to increase ROS levels in target cells? a. artemisinin b. amphotericin b c. praziquantel d. pleconaril

artemisinin

Which of the following drug classes specifically inhibits neuronal transmission in helminths? a. quinolines b. avermectins c. amantadines d. imidazoles

avermectins

Which of the following is a nucleoside analog commonly used as a reverse transcriptase inhibitor in the treatment of HIV? a. acyclovir b. ribavirin c. adenine-arabinoside d. azidothymidine

azidothymidine

Which of the following is not an appropriate target for antifungal drugs? a. ergosterol b. chitin c. cholesterol d. β(1→3) glucan

cholesterol

In the Kirby-Bauer disk diffusion test, the ______ of the zone of inhibition is measured and used for interpretation.

diameter

Which of the following resistance mechanisms describes the function of beta-lactamase? a. efflux pump b. target mimicry c. drug inactivation d. target overproduction

drug inactivation

Which of the following resistance mechanisms is commonly effective against a wide range of antimicrobials in multiple classes? a. efflux pump b. target mimicry c. target modification d. target overproduction

efflux pump

Which of the following resistance mechanisms is the most nonspecific to a particular class of antimicrobials? a. drug modification b. target mimicry c. target modification d. efflux pump

efflux pump

If drug A produces a larger zone of inhibition than drug B on the Kirby-Bauer disk diffusion test, drug A should always be prescribed.

false

Which of the following is not a type of beta-lactam antimicrobial? a. penicillins b. glycopeptides c. cephalosporins d. monobactams

gylcopeptides

The utility of an antibiogram is that it shows antimicrobial susceptibility trends ... a. over a large geographic area. b. for an individual patient. c. in research laboratory strains. d. in a localized population

in a localized population

Which of the following antimicrobials inhibits the activity of DNA gyrase? a. polymyxin B b. clindamycin c. nalidixic acid d. rifampin

nalidixic acid

Staphylococcus aureus, including MRSA strains, may commonly be carried as a normal member of the ________ microbiota in some people.

nasal

Antiviral drugs, like Tamiflu and Relenza, that are effective against the influenza virus by preventing viral escape from host cells are called ____________.

neuraminidase inhibitors

Which of the following routes of administration would be appropriate and convenient for home and administration of an antimicrobial to treat a systemic infection?

oral

Selective toxicity antimicrobials are easier to develop against bacteria because they are _________ cells, whereas human cells are eukaryotic.

prokaryotic

Which of the following terms refers to the ability of an antimicrobial drug to harm the target microbe without harming the host? a. mode of action b. therapeutic level c. spectrum of activity d. selective toxicity

selective toxicity

A scientist discovers that a soil bacterium she has been studying produces an antimicrobial that kills gram-negative bacteria. She isolates and purifies the antimicrobial compound, then chemically converts a chemical side chain to a hydroxyl group. When she tests the antimicrobial properties of the new version, she finds that this antimicrobial drug can now also kill gram-positive bacteria. The new antimicrobial drug with broad-spectrum activity is considered to be which of the following? a. resistant b. semisynthetic c. synthetic d. natural

semisynthetic

Which of the following has yielded compounds with the most antimicrobial activity?

soil

Which of the following does not bind to the 50S ribosomal subunit? a. tetracyclines b. lincosamides c. macrolides d. chloramphenicol

tetracyclines

Which clinical situation would be appropriate for treatment with a narrow-spectrum antimicrobial drug?

treatment of strep throat caused by culture identified Streptococcus pygenes

The rate of discovery of antimicrobial drugs has decreased significantly in recent decades.

true