10 Micro – Antimicrobial Treatment

Substances that are naturally produced by certain microorganisms that can inhibit or destroy other microorganisms are called
A. antibiotics.
B. narrow-spectrum drugs.
C. semi-synthetic drugs.
D. synthetic drugs.
E. broad-spectrum drugs.

A. antibiotics.

Antimicrobials effective against a wide variety of microbial types are termed
A. antibiotics.
B. narrow-spectrum drugs.
C. semisynthetic drugs.
D. synthetic drugs.
E. broad-spectrum drugs.

E. broad-spectrum drugs.

Antibiotics are derived from all of the following except
A. Penicillium.
B. Bacillus.
C. Staphylococcus.
D. Streptomyces.
E. Cephalosporium.

C. Staphylococcus.

Important characteristics of antimicrobial drugs include
A. low toxicity for human tissues.
B. high toxicity against microbial cells.
C. do not cause serious side effects in humans.
D. stable and soluble in body tissues and fluids.
E. All of the choices are correct.

E. All of the choices are correct.

The use of a drug to prevent imminent infection is called
A. competitive inhibition.
B. synergism.
C. prebiotics.
D. prophylaxis.
E. lantibiotics.

D. prophylaxis.

The use of any chemical in the treatment, relief, or prophylaxis of a disease is called
A. prophylaxis.
B. chemotherapy.
C. selective toxicity.
D. nephrotoxicity.
E. synergism.

B. chemotherapy.

Penicillins and cephalosporins
A. interfere with elongation of peptidoglycan.
B. block folic acid synthesis.
C. attach to the 30S ribosomal subunit and disrupt protein synthesis.
D. damage cell membranes.
E. block peptidases that cross-link glycan molecules.

E. block peptidases that cross-link glycan molecules.

Selective toxicity refers to
A. damage to pathogenic organisms.
B. damage to prokaryotic cell membranes.
C. damage to the target organisms but not host cells.
D. damage to nucleic acids.
E. None of the choices is correct.

C. damage to the target organisms but not host cells.

Each of the following effect cell walls except
A. penicillin.
B. cycloserine.
C. vancomycin.
D. erythromycin.
E. cephalosporin.

D. erythromycin.

Aminoglycosides
A. interfere with elongation of peptidoglycan.
B. block folic acid synthesis.
C. attach to the 30S ribosomal subunit and disrupt protein synthesis.
D. damage cell membranes.
E. block peptidases that cross-link glycan molecules.

C. attach to the 30S ribosomal subunit and disrupt protein synthesis.

Each of the following target prokaryotic ribosomes except
A. streptomycin.
B. gentamycin.
C. polymyxins.
D. tetracycline.
E. erythromycin.

C. polymyxins.

Drugs that insert on the _____ ribosomal subunit prevent peptide bond formation or inhibit translocation of the subunit during translation.
A. 30S
B. 40S
C. 50S
D. 60S
E. 70S

C. 50S

Sulfonamides
A. interfere with elongation of peptidoglycan.
B. block folic acid synthesis.
C. attach to the 30S ribosomal subunit and disrupt protein synthesis.
D. damage cell membranes.
E. block peptidases that cross-link glycan molecules.

B. block folic acid synthesis.

Sulfa drugs work on
A. nucleic acid biosynthesis.
B. ribosome biosynthesis.
C. peptidoglycan biosynthesis.
D. folic acid biosynthesis.
E. None of the choices is correct.

D. folic acid biosynthesis.

Sulfonamides are analogs of PABA and, as a result, they inhibit _____ synthesis.
A. protein
B. DNA
C. RNA
D. folic acid
E. phospholipid

D. folic acid

Drugs that act by mimicking the normal substrate of an enzyme, thereby blocking its active
site, are called
A. inhibitors.
B. blockers.
C. competitive inhibitors.
D. noncompetitive inhibitors.
E. None of the choices is correct.

C. competitive inhibitors.

Ampicillin, amoxicillin, mezlocillin, and penicillin G all have
A. a beta-lactam ring.
B. resistance to the action of penicillinase.
C. a semisynthetic nature.
D. an expanded spectrum of activity.
E. All of the choices are correct.

A. a beta-lactam ring.

A chemical that inhibits beta-lactamase enzymes is
A. synercid.
B. penicillinase.
C. aztreonam.
D. clavulanic acid.
E. imipenem.

D. clavulanic acid.

What type of chemical will allow some bacteria to be resistant to many penicillins?
A. synercid
B. penicillinase
C. aztreonam
D. clavulanic acid
E. imipenem

B. penicillinase

All of the following pertain to cephalosporins except
A. have a beta-lactam ring.
B. greater resistance to beta-lactamases.
C. newer generations have activity against gram-negatives.
D. many administered by injection, not orally.
E. are synthetic drugs.

E. are synthetic drugs.

Which antimicrobial does not inhibit cell wall synthesis?
A. gentamicin
B. vancomycin
C. cephalosporins
D. penicillins
E. clavamox

A. gentamicin

Which drug is used to treat cases of tuberculosis?
A. penicillin G
B. vancomycin
C. tetracycline
D. synercid
E. isoniazid

E. isoniazid

What drug is used in cases of penicillin and methicillin resistance and also used to treat endocarditis?
A. penicillin G
B. vancomycin
C. tetracycline
D. erythromycin
E. isoniazid

B. vancomycin

Clavulanic acid
A. inhibits B-lactamase activity.
B. inhibits peptidoglycan synthesis.
C. inhibits formation of peptidoglycan cross linkages.
D. inhibits cell membrane synthesis.
E. None of the choices is correct.

A. inhibits B-lactamase activity.

All _____ consist of a thiazolidine ring, a beta-lactam ring, and an R group.
A. penicillins
B. tetracyclins
C. macrolides
D. cephalosporins
E. aminoglycosides

A. penicillins

The major source of naturally produced penicillin is the mold
A. Penicillium notatum.
B. Penicilium chrysogenum.
C. Penicilium familiaris.
D. Naturally produced penicillin is no longer used.
E. None of the choices is correct.

B. Penicilium chrysogenum.

Gram-negative rods are often treated with
A. penicillin G.
B. vancomycin.
C. aminoglycosides.
D. synercid.
E. isoniazid.

C. aminoglycosides.

Which antimicrobial does not interfere with protein synthesis?
A. aminoglycosides
B. tetracyclines
C. erythromycin
D. trimethroprim
E. gentamicin

D. trimethroprim

Which of these drugs has the most narrow spectrum?
A. tetracycline
B. isoniazid
C. erythromycin
D. aminoglycosides
E. cephalosporins

B. isoniazid

Antimicrobials that are macrolides
A. disrupt cell membrane function.
B. include tetracyclines.
C. include azithromycin, clarithromcyin and erythromycin.
D. are very narrow-spectrum drugs.
E. are hepatotoxic.

C. include azithromycin, clarithromcyin and erythromycin.

The drug that can cause injury to red blood cells and white blood cells is
A. chloramphenicol.
B. clindamycin.
C. ciprofloxacin.
D. bacitracin.
E. gentamicin.

A. chloramphenicol.

Which of the following antibacterial drug groups does not target protein synthesis?
A. clindamycin
B. erythromycin
C. aminoglycosides
D. sulfonamides
E. tetracycline

D. sulfonamides

Which antibiotic is used to treat MRSA and VRE infections?
A. synercid
B. clindamycin
C. linezolid
D. azithromycin
E. clarithromycin

C. linezolid

Which of the following is not true of polymyxins?
A. disrupt the cell membrane
B. have a narrow-spectrum
C. toxic to kidneys
D. target cell walls
E. can treat severe urinary tract infections

D. target cell walls

The antifungal drug that can be used to treat serious systemic fungal infections is
A. nystatin.
B. griseofulvin.
C. amphotericin B.
D. sulfa drugs.
E. metronidazole.

C. amphotericin B.

Ketoconazole, fluconazole, clotrimazole and miconazole are broad-spectrum azoles used to treat _____ infections.
A. bacterial
B. fungal
C. protozoan
D. helminthic
E. viral

B. fungal

Which of the following is not a drug group used to treat fungal infections?
A. quinolones
B. macrolide polyene antibiotics
C. griseofulvins
D. synthetic azoles
E. flucytosines

A. quinolones

The drug used for several protozoan infections is
A. nystatin.
B. griseofulvin.
C. amphotericin B.
D. sulfa drugs.
E. metronidazole.

E. metronidazole.

Mebendazole is a drug used to treat _____ infections.
A. bacterial
B. fungal
C. protozoan
D. helminthic
E. viral

D. helminthic

There are fewer antifungal, anti-protozoan, and anti-helminth drugs compared to antibacterial drugs because fungi, protozoa, and helminths
A. do not cause many human infections.
B. are not affected by antimicrobials.
C. are so similar to human cells that drug selective toxicity is difficult.
D. are parasites found inside human cells.
E. because their cells have fewer target sites compared to bacteria.

C. are so similar to human cells that drug selective toxicity is difficult.

Primaquine and chloroquine are drugs used in the treatment of
A. gram-positive infections.
B. gram-negative infections.
C. fungal infections.
D. protozoan infections.
E. viral infections.

D. protozoan infections.

Which of the following is not a mode of action of antiviral drugs?
A. block penetration
B. block transcription and translation
C. inhibit DNA synthesis
D. block maturation
E. bond to ergosterol in the cell membrane

E. bond to ergosterol in the cell membrane

An antiviral that is a guanine analog would have an antiviral mode of action that
A. blocks penetration.
B. blocks transcription and translation.
C. inhibits DNA synthesis.
D. blocks maturation.
E. bonds to ergosterol in the cell membrane.

C. inhibits DNA synthesis.

Antiviral drugs that target reverse transcriptase would be used to treat
A. influenza A virus.
B. HIV.
C. herpes zoster virus.
D. respiratory syncytial virus.
E. hepatitis C virus.

B. HIV.

Acyclovir is used to treat
A. influenza A virus.
B. HIV.
C. herpes simplex virus.
D. respiratory syncytial virus.
E. hepatitis C virus.

C. herpes simplex virus.

Which of the following block HIV binding to host cell receptors?
A. AZT
B. acyclovir
C. nevirapine
D. fuzeon
E. amantidine

D. fuzeon

The cellular basis for bacterial resistance to antimicrobials include
A. bacterial chromosomal mutations.
B. synthesis of enzymes that alter drug structure.
C. prevention of drug entry into the cell.
D. alteration of drug receptors on cell targets.
E. All of the choices are correct.

E. All of the choices are correct.

The multidrug resistant pumps in many bacterial cell membranes function by
A. bacterial chromosomal mutations.
B. synthesis of enzymes that alter drug structure.
C. removing the drug from the cell when it enters.
D. alteration of drug receptors on cell targets.
E. All of the choices are correct.

C. removing the drug from the cell when it enters.

Microbial resistance resulting from mutation occurs because
A. prokaryotic genomes undergo mutation rapidly.
B. prokaryotic genomes undergo mutation often.
C. short generation times accumulate mutations in populations.
D. mutations are passed between organisms.
E. All of the choices are correct.

E. All of the choices are correct.

Each of the following result in drug resistance except
A. drug pumped out of the cell.
B. drug used as a nutrient by the cell.
C. drug binding site altered.
D. drug inactivated.
E. drug blocked from entering cell.

B. drug used as a nutrient by the cell.

Each of the following is a mechanism for drug resistance transfer between microorganisms except
A. transposons.
B. R-plasmids.
C. conjugation.
D. mutation.
E. All of the choices provide for transfer of drug resistance.

D. mutation.

Each of the following contributes to emerging drug resistance except
A. overuse of antibiotics.
B. improper use of antibiotics.
C. multiple drug therapy.
D. ingestion of antibiotics with animal feed.
E. addition of antibiotics to common household products.

C. multiple drug therapy.

Nutrients that encourage the growth of beneficial microbes in the intestines are known as
A. prebiotics.
B. probiotics.
C. lantibiotics.
D. phytobiotics.
E. riboswitches.

A. prebiotics.

The use of vaginal inserts of Lactobacillus to restore a healthy acidic environment is an example of
A. prebiotics.
B. probiotics.
C. lantibiotics.
D. phytobiotics.
E. riboswitches.

B. probiotics.

Broad-spectrum drugs that disrupt the body’s normal flora often cause
A. nephrotoxicity.
B. superinfections.
C. allergic reactions.
D. drug toxicity.
E. All of the choices are correct.

B. superinfections.

Side effects that occur in patient’s tissues while on antimicrobial drugs include all the following except
A. development of resistance to the drug.
B. hepatotoxicity.
C. nephrotoxicity.
D. diarrhea.
E. deafness.

A. development of resistance to the drug.

A superinfection results from
A. build up of a drug to toxic levels in the patient.
B. the wrong drug administered to the patient.
C. an immune system reaction to the drug.
D. decrease in most normal flora with overgrowth of an unaffected species.
E. All of the choices are correct.

D. decrease in most normal flora with overgrowth of an unaffected species.

The _____ are drugs that deposit in developing teeth and cause a permanent brown discoloration.
A. streptomycins
B. cephalosporins
C. macrolides
D. tetracyclins
E. penicillins

D. tetracyclins

Drug susceptibility testing determines
A. the patient’s response to various antimicrobials.
B. the pathogen’s response to various antimicrobials.
C. if normal flora will be affected by antimicrobials.
D. if the drug is increasing to toxic levels in a patient.
E. None of the choices is correct.

B. the pathogen’s response to various antimicrobials.

A clinical microbiologist makes serial dilutions of several antimicrobials in broth, and then incubates each drug dilution series with a standard amount of a patient’s isolated pathogen. What is this microbiologist setting up?
A. Kirby-Bauer
B. antibiogram
C. E-test
D. MIC
E. therapeutic index (TI)

D. MIC

A ratio of the dose of the drug that is toxic to humans versus the minimum effective dose for that pathogen is assessed to predict the potential for toxic drug reactions. This is called the
A. Kirby-Bauer.
B. antibiogram.
C. E-test.
D. MIC.
E. therapeutic index (TI).

E. therapeutic index (TI).

If pathogen A is more resistant to an erythromycin disc on a Kirby-Bauer plate compared to pathogen B, then pathogen A will have a(n) _____ zone of inhibition compared to pathogen B.
A. smaller
B. equal
C. larger
D. All of the choices are correct.
E. None of the choices is correct.

A. smaller

Which therapeutic index value would be the drug of choice?
A. 20
B. 10
C. 1
D. 0.1
E. Any value would be equally effective.

A. 20

Which two antibiotics affect the DNA and RNA of bacteria?
A. tetracycline and amphotericin B
B. trimethoprim and sulfonamides
C. Rifampin and quinolones
D. tetracycline and bacitracin

C. Rifampin and quinolones

Antimicrobial drugs that inhibit folic acid synthesis work with no side effects because mammals must get folic acid from their diet.

true

Species of Bacillus produce bacitracin and the polymyxins.

true

An antibiotic of the penicillin family is penicillin G.

true

The first modern antimicrobial drugs were sulfa drugs.

true

Ciprofloxacin is used to treat viral respiratory infections.

false

Resistance factor plasmids are transferred to other bacterial cells during transformation,
transduction, and conjugation.

true

Bacteria can have a natural resistance to a drug that it has never been exposed to.

true

When a patient’s immune system reacts adversely to a drug, this serious side effect is called a superinfection.

false

Drugs that are hepatotoxic cause damage to a patient’s kidneys.

false

The MIC is the smallest concentration of an antimicrobial required to inhibit the growth of the microbe.

true

The Kirby-Bauer test uses an agar surface, seeded with the test bacterium, to which small discs containing a specific concentration of several drugs are placed on the surface.

true

An antimicrobial with a low therapeutic index is a safer choice compared to a drug with a high therapeutic index.

false

It is better to use a broad-spectrum drug instead of a more specific narrow-spectrum drug.

false

Newer, more expensive antimicrobials are always better to use than cheaper, older drugs.

false

Indwelling catheter biofilm infections are more resistant to antibiotics than non-biofilm infections.

true

Drug toxicity occurs when an antimicrobial drug acts as antigen and stimulates an allergic response.

false