Microbiology Chapter 20:Antimicrobial Drugs

Which of the following will NOT affect eukaryotic cells A. inhibition of the mitotic spindle B. binding with sterols C. binding to 80s ribosomes D. binding to DNA E. All of the above will affect them

All of the above will affect them

Important characteristics of antimicrobial drugs include A. Stable and soluble in body tissues and fluids B. High toxicity against microbial cells C. Do not cause serious side effects in humans D. All of the choices are correct

All of the choices are correct

Antimicrobial drugs that are derived from the natural processes of some microorganisms and that can inhibit or destroy other microorganisms are specifically known as what? A) Chemotherapeutic drugs B) Prophylactic drugs C) Semisynthetic drugs D) Synthetic drugs E) Antibiotics

Antibiotics

There are fewer antifungal, antiprotozoan and antihelminth 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

Are so similar to human cells that drug selective toxicity is difficult

Bacterial infections are easier to treat using chemotherapy than are other types of infections. Why? A. Bacteria are prokaryotic. B. Bacteria are more sensitive to chemicals. C. Bacteria grow more slowly. D. Bacteria are smaller than the other types of pathogens

Bacteria are prokaryotic

Why do fungal infections present special problems in terms of treatment? A) Because fungi have cell walls composed of cellulose or chitin B) Because both fungi and humans are eukaryotes C) Because fungi do not have an outer membrane D) Because fungi are encapsulated E) Because fungi do not have a nucleus

Because both fungi and humans are eukaryotes

Why are viral infections especially difficult to treat? A) Because they rely upon their host cells for the majority of their metabolic functions B) Because they can have RNA as their nucleic acid C) Because some viruses are naked while others are enveloped D) Because there are many types of viral structures E) Because viruses can halt their metabolism when in the presence of an antiviral agent

Because they rely upon their host cells for the majority of their metabolic functions

In what way are semisynthetic penicillins and natural penicillins alike? A. Both are resistant to stomach acids. B. Both are based on β-lactam. C. Both are bactericidal. D. Both are resistant to penicillinase. E. Both are broad spectrum

Both are based on β-lactam

Which drug is known to lead to superinfection or cause opportunistic infections A. narrow spectrum antibiotics B. Broad spectrum antibiotics

Broad spectrum antibiotics

What is meant by selective toxicity? A. Chemotherapeutic agents should act against the pathogen and not the host. B. Chemotherapeutic agents should work on many different targets on a pathogen. C. Chemotherapeutic agents should have only one mode of action. D. Chemotherapeutic agents should work on certain types of pathogens.

Chemotherapeutic agents should act against the pathogen and not the host

Which of the following is used only in life-threatening situations when no other drug is adequate? A) Cephalosporin B) Penicillin C) Tetracycline D) Chloramphenicol E) Streptomycin

Chloramphenicol

Quinolones and fluoroquinolones act against what bacterial target? A. Cell membranes B. Cell walls C. Bacterial ribosomes D. DNA gyrase E. Metabolic pathways unique to bacteria

DNA gyrase

How developed the concept of specific toxicity? A) Jenner B) Pasteur C) Fleming D) Watson E) Ehrlich

Ehrlich

True/ False PABA serves as the competitive inhibitor in the action of sulfanilamides

False

True/ False Penicillin and streptomycin are commonly used in syngerism because they display the same mode of action.

False

True/ False Phage therapy has been used in the past as an antiviral treatment.

False

True/False A drug that inhibits translation at 70S ribosomes can be used to treat human viral infections

False

True/False Alexander Fleming performed the first clinical trials with penicillin, demonstrating its effectiveness as a chemotherapeutic agent

False

True/False Bacteriostatic agents are ineffective as antibiotics

False

True/False It is relatively easy to find drugs that are effective against eukaryotic pathogens

False

True/False Ivermectin is an anti-protozoan drug.

False

True/ False Penicillinase - resistant penicillins are effective against gram-negative organisms

False. These antibiotics are used for gram-positive bacteria, especially those that produced penicillinase.

Which of the following is mismatched? A. Ehrlich - magic bullet theory B. Florey and Chain - identification of Penicillium as the producer of penicillin C. Fleming - identification of penicillin D. None of these is mismatched. E. Kirby and Bauer - disc-diffusion method

Florey and Chain - identification of Penicillium as the producer of penicillin

Why are chemotherapeutic agents that work on the peptidoglycan cell wall of bacteria a good choice of drug? A. Bacteria are especially sensitive to these compounds. B. The drugs also work against DNA gyrase. C. They are less expensive that other chemotherapeutic agents. D. Humans and other animal hosts lack peptidoglycan cell walls.

Humans and other animal hosts lack peptidoglycan cell walls

Which mode of antibiotic activity is the most selective target for antibiotics since it will not affect eukaryotic cells? A. Injury to the plasma membrane B. Inhibition of cell wall synthesis C. Inhibition of transcription D. Inhibition of DNA replication E. Inhibition of translation

Inhibition of cell wall synthesis

Why is polymyxin only used on the skin? A. It is sensitive to degradation by acid, making oral delivery unsuitable. B. It has no effect on bacteria that live in the GI tract. C. It can also damage living human cell membranes, but the drug is safely used on the skin, where the outer layers of cells are dead. D. It can disrupt the metabolic pathways found in humans.

It can also damage living human cell membranes, but the drug is safely used on the skin, where the outer layers of cells are dead.

What is the benefit of combining penicillins with potassium clavulanate? A. It makes penicillin more stable in stomach acid. B. It inhibits penicillinase. C. It decreases potency of penicillin. D. It increases the spectrum of activity

It inhibits penicillinase

The __________ test is a commonly used disk-diffusion method for evaluating antibiotic effectiveness

Kirby-Bauer

Chloroquine-resistant malaria may be treated with __________.

Mefloquine

Which of the following statements about antibiotics is true? A. The finding of antibiotic-producing microorganisms is a rare event. B. Most of our antibiotics are produced by Streptomyces, a genus of filamentous soil bacteria. C. Penicillin was first discovered by two researchers named Florey and Chain. D. Antibiotics are not typically produced by microorganisms growing in their natural environment.

Most of our antibiotics are produced by Streptomyces, a genus of filamentous soil bacteria

Although several classes of antibacterial drugs act by inhibiting protein synthesis, only one acts by inhibiting the actual initiation of protein synthesis. What is this class of drugs? A) Sulfonamides B) Chloramphenicol C) Vancomycin D) Fluoroquinolones E) Oxazolidinones

Oxazolidinones

The golden age of antibiotics began in 1928 with Sir Alexander Fleming's discovery of an antibacterial compound he called what? A) Arsenic B) Salvarsan C) Sulfonamide D) Penicillin E) Tetracycline

Penicillin

Which antibacterial drug does not inhibit protein synthesis? A) Aminoglycoside B) Tetracycline C) Penicillin D) Chloramphenicol E) Erythromycin

Penicillin

Which antibiotic has a beta-lactam ring? A) Cephalosporin B) Penicillin C) Tetracycline D) Chloramphenicol E) Streptomycin

Penicillin

Which of the following is NOT a semisynthetic chemotherapeutic agent? A) Ampicillin B) Carbenicillin C) Methicillin D) Penicillin E) Sulfonamide

Penicillin

The greatest number of antimicrobic allergies is reported for what drug? A) Sulfonamides B) Tetracycline C) Quinolones D) Penicillins E) Pyrantel

Penicillins

Which of the following is NOT a reason for the selective toxicity of sulfa drugs? A. Sulfa drugs inhibit a bacterial enzyme. B. Sulfa drugs cause production of antimetabolites. C. Humans get folic acid from their diet; they do not synthesize it. D. Bacteria must synthesize folic acid

Sulfa drugs cause production of antimetabolites

What was the first disease to be treated with a specific chemical? A) Tuberculosis B) Syphilis C) Bacterial meningitis D) Whooping cough E) Scarlet fever

Syphilis

While observing the results of a disk-diffusion susceptibility test, you note an enlarged oval zone of inhibition around two adjacent antibiotic disks. Which of the following is the most likely explanation? A. The two antibiotics are antagonistic. B. The two antibiotics are bacteriostatic. C. The two antibiotics are bactericidal. D. The two antibiotics are synergistic.

The two antibiotics are synergistic

Which of the following is untrue of the cephalosporin group of drugs? A) Their structure is similar to that of the penicillins. B) Their spectrum of activity is extremely narrow. C) There are three generations of these drugs. D) They cause fewer allergic reactions than the penicillins. E) They have two possible sites for placement of variable side chains.

Their spectrum of activity is extremely narrow

There are a large number of antibiotics that inhibit protein synthesis at 70s ribosomes found in bacterial cells but do not interfere with protein synthesis at the 80s ribosomes found in eukaryotic cells. Some of these antibiotics bind to the smaller ribosomal subunit and interfere with the reading of the mRNA code, whereas others bind to the larger ribosomal subunit and inhibit the formation of peptide bonds. Unfortunately, some of the antibiotics that inhibit protein synthesis in bacteria exhibit some toxicity to the eukaryotic host cells as well. What is the most likely reason for this toxicity to the host cell? A. These antibiotics bond to eukaryotic tRNA. B. These antibiotics bind to eukaryotic cytoplasmic ribosomes. C. These antibiotics interfere with protein synthesis within eukaryotic mitochondria. D. These antibiotics interfere with DNA replication in eukaryotic cell nuclei. E. These antibiotics plug up the membrane transport mechanisms in eukaryotic cells.

These antibiotics interfere with protein synthesis within eukaryotic mitochondria

Which of the following statements is true about superinfections? A. They are caused by antibiotic-resistant bacteria. B. They inhibit protein synthesis. C. They only occur in people with immunodeficiencies. D. They are caused by endospore-forming bacteria.

They are caused by antibiotic-resistant bacteria

Which one is a diadvantage of broad spectrum antibiotics A. The drug affect few bacteria B. It takes longer for the drug to work C. They destroy many of the the host's normal microbiota D. These drugs are lipophilic and have a difficult time entering bacteria through the cell wall

They destroy many of the the host's normal microbiota

Which of the following statements is true about superinfections? A. They are caused by endospore-forming bacteria. B. They occur only in people who have immunodeficiencies. C. They inhibit protein synthesis. D. They may be caused by antibiotic-resistant bacteria.

They may be caused by antibiotic-resistant bacteria

Which of the categories of antimicrobial drugs exhibits the least degree of selective toxicity? A) Those that disrupt cell membrane function B) Those that affect the cell wall C) Those that inhibit nucleic acid function D) Those that inhibit protein synthesis E) Those that inhibit nucleic acid synthesis

Those that disrupt cell membrane function

Which of the following is not a category of antimicrobial drugs? A) Those that inhibit cell wall synthesis B) Those that inhibit DNA and RNA structure and function C) Those that inhibit protein synthesis D) Those that interfere with cell membrane structure and function E) Those that inhibit mRNA processing in the nucleus

Those that inhibit mRNA processing in the nucleus

The drug, flagyl, is commonly used to treat an STD caused by ________. A. Trichomonas vaginalis B. Neisseria gonorrhoeae C. herpesvirus D. HIV E. Treponema pallidum

Trichomonas vaginalis

True/ False An antibiotic that attacks the LPS layer would be expected to have a narrow spectrum of activity

True

True/ False Antibiotics targeting 70s ribosomes can have an adverse effect on the cells of the host

True

True/ False Antiviral drugs target viral processes that occur during viral infection.

True

True/False Antibiotic resistance can be minimized by the discriminating use of drugs in appropriate dosages

True

True/False Because antifungal drugs like amphotericin B target sterols in the plasma membrane, they are ineffective as antibacterial drugs

True

True/False Semisynthetic penicillins are more effective antibiotics than is natural penicillin

True

True/False Some drug combinations are synergistic; therefore, when taken together, they are more effective

True

True/False The MIC is the lowest concentration of drug capable of preventing microbial growth

True

Why is it difficult to find good chemotherapeutic agents against viruses? A. There is no effective way to deliver the drug to the virus. B. Viruses infect both bacteria and human cells. C. Viruses are not cells, and therefore not sensitive to such compounds. D. Viruses depend on the host cell's machinery, so it is hard to find a viral target that would leave the host cell unaffected

Viruses depend on the host cell's machinery, so it is hard to find a viral target that would leave the host cell unaffected

In the disk-diffusion, what do the clear areas around the discs represent? A. Where the bacteria are growing the fastest. B. Where drug-resistant mutants are located. C. It is impossible to determine from the information given. D. Where bacterial growth has been inhibited.

Where bacterial growth has been inhibited

Drugs that affect the bacterial cell wall are active only against what type of cells? A) Gram negative B) Dormant C) Young, actively growing D) Endospore-forming E) Gram variable

Young, actively growing

Which is an antiviral drug used to treat herpes infections? A) acyclovir B) neomycin

acyclovir Acyclovir is an antiviral drug used to treat herpes infections, which inhibits DNA synthesis in an infected cell.

A disk-diffusion test identifies __________. A. minimal bactericidal concentration (MBC) B. bacteriostatic agents only C. agents to which a test culture is sensitive, in terms of growth or survival D. bactericidal agents only

agents to which a test culture is sensitive, in terms of growth or survival

A disk-diffusion test identifies: A. MBC. B. agents to which a test culture is susceptible. C. bacteriostatic agents. D. bactericidal agents.

agents to which a test culture is susceptible

Which class of drug's usefulness is often limited by its toxic side effects, which include hearing and kidney damage?

aminoglycosides

Which group of antibiotics targets protein synthesis? A) aminoglycosides B) the fluoroquinolones

aminoglycosides Aminoglycosides, like streptomycin, target protein synthesis

Which of the following antibiotics should be prescribed as a first choice for a streptococcal infection? A. rifampin B. tetracycline C. trimethoprim D. amoxicillin E. neomycin

amoxicillin

Which of these is an antifungal drug? A) amphotericin B B) isoniazid

amphotericin B Amphotericin B is an antifungal drug that targets the cell membrane

A drug that inhibits peptidoglycan synthesis is __________. A. antibacterial B. antifungal C. antiviral D. antiprotozoan

antibacterial

A drug that inhibits peptidoglycan synthesis is: A. antifungal. B. antibacterial. C. antiviral. D. antiprotozoal.

antibacterial

Which of the following pairs is mismatched A. antihelminthic-inhibition of oxidative phosphorylation B. antihelminthic - inhibition of cell wall synthesis C. antifungal - injury to plasma membrane D. antifungal - inhibition to mitosis E. antiviral - inhibition to DNA synthesis

antihelminthic - inhibition of cell wall synthesis

Antibiotics that inhibit translation have side effects A. because all cells have proteins B. only in the few cells that make proteins C. because eukaryotic cells have 80s ribosomes D. at the 70s ribosomes in eukaryotic cells E. none of the above

at the 70s ribosomes in eukaryotic cells

The most selective antibiotics are those that interfere with the synthesis of A) bacterial DNA. B) bacterial RNA. C) bacterial cell walls. D) bacterial plasma membrane. E) bacterial pili.

bacterial cell walls

Which of the following is NOT a mechanism by which antibiotic resistance spreads horizontally among bacteria? A. transduction B. bacterial conjugation C. plasmid transfer D. bacterial transcription

bacterial transcription

What do we call a drug that inhibits bacterial growth

bacteriostatic

A chemical that kills gram-positive bacteria and gram-negative bacteria would best be described as __________. A. broad spectrum B. selectively toxic C. narrow spectrum D. specific

broad spectrum

An antibiotic that targets both gram-positive and gram-negative bacteria would be A) broad spectrum B) narrow spectrum

broad spectrum A broad spectrum antibiotic targets a wide range of both gram-positive and gram-negative bacteria.

Quinolones are A) antimetabolites. B) penicillin derivatives. C) bacteristatic. D) broad-spectrum. E) narrow-spectrum

broad-spectrum

Which of the following types of antibiotics is most likely to be associated with the development of a superinfection? A. beta-lactam antibiotics B. bacteriostatic antibiotics C. bactericidal antibiotics D. narrow-spectrum antibiotics E. broad-spectrum antibiotics

broad-spectrum antibiotics

Cell membrane damage causes death because A. the cell undergoes osmotic lysis B. cell contents leak out C. the cell plasolyzes D. the cell lacks a wall E. none of the above

cell contents leak out

Because gram-positive cells have more peptidoglycan, it makes these cells more susceptible to which type of antibiotic A. Protein synthesis B. cell wall C. Injuring plasma membrane D. Nucleic acid synthesis E. Enzyme snthesis

cell wall

Penicillins and cephalosporins use this mode of action when attacking a bacterial A. Protein synthesis B. cell wall C. Plasma membrane D. Nucleic acid synthesis E. Enzyme snthesis

cell wall

Since humans do not have peptidoglycan, antibiotics that inhibit this are less toxic. A. Protein synthesis B. cell wall C. plasma membrane D. Nucleic acid synthesis E. Enzyme snthesis

cell wall

This is a selective target site because only bacteria contain peptidoglycan. A. Protein synthesis B. cell wall C. Plasma membrane D. Nucleic acid synthesis E. Enzyme snthesis

cell wall

Which is the drug of choice for the treatment of malaria? A. flagyl B. nifurtimox C. iodoquinol D. quinacrine E. chloroquine

chloroquine

Which drug gained widespread publicity for its use against anthrax infections?

ciprofloxacin or cipro

Which drug would be used to treat athlete's foot? A. polymyxin B B. clotrimazole C. neomycin D. amantadine E. chloroquine

clotrimazole

Penicillin prevent the cross-linking of the peptidoglycans, which interfers with the final stages of A. Protein synthesis B. constructing the cell wall C. plasma membrane D. Nucleic acid synthesis E. Enzyme snthesis

constructin the cell wall

Antimicrobial peptides work by A. hydrolyzing peptidoglycan. B. disrupting the plasma membrane. C. inhibiting protein synthesis. D. inhibiting cell-wall synthesis. E. complementary base pairing with DNA

disrupting the plasma membrane

Which of the following antibiotics is frequently used as an alternative for those who are allergic to penicillin? A. ethambutol B. streptomycin C. vancomycin D. amoxicillin E. erthryomycin

erthryomycin

Which of the following would be selective against the tubercle bacillus? A. ethambutol - inhibits mycolic acid synthesis B. vancomycin - inhibits peptidoglycan synthesis C. bacitracin - inhibits peptidoglycan synthesis D. streptomycin - inhibits protein synthesis E. streptogramin - inhibits protein synthesis

ethambutol - inhibits mycolic acid synthesis

A drug that binds with sterols would injure __________. A. DNA B. fungal cell walls C. eukaryotic plasma membranes D. bacterial cell walls

eukaryotic plasma membranes Sterols are found in eukaryotic cell membranes

True/False The enzyme penicillinase pumps penicillin out of the bacterial cell before it affects the cell

false

True/False The only useful target for antibiotics is the bacterial cell wall

false

True/False There are more drugs that are antiviral than antimicrobial

false.

Which antifungal drug is commonly used for systemic fungal infections? A. tolnaftate B. fluconazole C. miconazole D. amphotericin B E. clotrimazole

fluconazole

Polyenes, azoles, and allylamines interfere with __________. A. viruses B. cell walls in gram-negative bacteria C. fungal cell membranes D. cell membranes in gram-positive bacteria

fungal cell membranes

A drug that inhibits mitosis, such as griseofulvin, would be more effective against A. wall-less bacteria. B. mycobacteria. C. gram-negative bacteria. D. fungi. E. gram-positive bacteria

fungi

Tetracyclines are effective against all of the following except ________. A. fungi B. gram-positive bacteria C. gram-negative bacteria D. intracellular rickettsias E. intracellular chlamydias

fungi

Tetracyclines are effective against all of the following except: A.intracellular rickettsias. B. Gram-negative bacteria. C. Gram-positive bacteria. D. fungi. E. intracellular chlamydias

fungi

An antimicrobial drug that inhibits peptidoglycan synthesis is most likely to be effective against ________. A. gram-positive bacteria B. viruses C. gram-negative bacteria D. fungi E. protozoan parasites

gram-positive bacteria

Niclosamide prevents ATP generation in mitochondria. You would expect this drug to be effective against A. gram-negative bacteria. B. viruses. C. helminths. D. Mycobacterium tuberculosis. E. gram-positive bacteria

helminths

All of the following are modes of action of antiviral drugs EXCEPT A. inhibiotn of protein synthesis 70s ribosomes B. inhibition of DNA synthesis C. inhibition of RNA synthesis D. inhibition of uncoating E. none of the above

inhibiotn of protein synthesis 70s ribosomes

Which of the following mechanisms is antifungal? A. inhibit ergosterol synthesis B. interfere with anaerobic metabolism C. inhibit 70S ribosomes D. inhibit peptidoglycan synthesis E. cause muscle spasms

inhibit ergosterol synthesis

What is the method of action of nucleoside analogs? A. disruption of plasma membrane B. inhibition of DNA synthesis C. inhibition of protein synthesis D. inhibition of cell wall synthesis

inhibition of DNA synthesis

Which of the following modes of action would not be fungicidal A. inhibition of peptidoglycan synthesis B. injury to the plasma mebrane C. inhibition of mitosis D. inhibition of nucleic acid synthesis E. none of the above

inhibition of peptidoglycan synthesis

Which of the following methods of action would be bacteriostatic? A. inhibition of protein synthesis B. competitive inhibition with DNA gyrase C. inhibition of cell wall synthesis D. competitive inhibition with folic acid synthesis E. injury to plasma membrane

inhibition of protein synthesis

The most selective antimicrobial activity would be exhibited by a drug that A. inhibits cell wall synthesis B. inhibits protein synthesis C. injures the plasma membrane D. inhibits nucleic acid synthesis E. all of the above

inhibits cell wall synthesis

Which antimicrobial works by inhibiting the synthesis of mycolic acid? A. methicillin B. vancomycin C. chloramphenicol D. penicillin E. isoniazid

isoniazid

Which antimicrobial is used to treat tuberculosis? A) gentamicin B) isoniazid

isoniazid Isoniazid and ethambutol are effective against mycobacteria

In the presence of penicillin, a cell dies because A. it plasmolyzes. B. it undergoes lysis. C. it lacks a cell membrane. D. it lacks a cell wall. E. its contents leak out

it undergoes lysis.

Which of the following is an antihelminthic drug that causes paralysis of the worm? A. ivermectin B. niclosamide C. praziquantel D. mebendazole

ivermectin

All of the following are anti-protozoan drugs except ________. A. chloroquine B. metronidazole C. mefloquine D. quinacrine E. mebendazole

mebendazole

Ethambutol inhibits incorporation of mycolic acid into cell walls; therefore, it is effective against __________. A. fungi B. mycoplasmas C. gram-positive bacteria D. mycobacteria

mycobacteria

If a drug affects relatively few bacteria it is A. narrow spectrum B. Broad spectrum

narrow spectrum

Which drug is present in many nonprescription topical preparations? A) amoxicillin B) neomycin

neomycin

Which of the following is a broad-spectrum, topical antibacterial compound? A. caspofungin B. polymyxin B C. neomycin D. bacitracin

neomycin

Which drug is not a nucleoside analog? A. ribavirin B. lamivudine C. zidovudine D. neviraprine E. acyclovir

neviraprine

Which of the following is used for treating influenza infections? A. acyclovir B. pentamidine isethionate C. interferon D. indinivir E. oseltamivir

oseltamivir

Which of the following antimicrobial agents has the fewest side effects? A. penicillin B. chloramphenicol C. streptomycin D. tetracycline E. erythromycin

penicillin

The first true antibiotic discovered was A) salvarsan B) penicillin

penicillin Penicillin was the first antibiotic, discovered from a colony of mold on a Petri dish

Bacteria resistant to penicillins produce an enzyme called __________ that cleaves the beta-lactam ring of the drug.

penicillinase

Which of the following may carry antibiotic resistance genes? A) the Beta lactam ring B) plasmids

plasmids Plasmids are circular DNA molecules that may carry antibiotic resistance genes

Which antibiotic target is useful due to its differences in prokaryotes and eukaryotes? A) DNA B) ribosomes

ribosomes

Which of the following drugs inhibits the synthesis of mRNA in bacteria? A. polymyxin B B. rifampin C. ethambutol D. trimethoprim E. ampicillin

rifampin

Which drug did Paul Ehrlich discover to treat syphilis? A) vancomycin B) salvarsan

salvarsan

Most antibiotics are isolated from A) viruses. B) fungi. C) aquatic microorganisms. D) soil microorganisms. E) plants

soil microorganisms

Many antifungal drugs target __________ in the fungal cell membrane

sterols

Which of the following antibiotics inhibits protein synthesis? A. vancomycin B. isoniazid C. cephalosporin D. streptomycin E. rifampin

streptomycin

Which one of the following does NOT belong with the others? A. streptomycin B. penicillin C. monobactam D. cephalosporin E. bacitracin

streptomycin

Which of the following antibiotics inhibits folic acid synthesis? A. tetracycline B. neomycin C. ampicillin D. chloramphenicol E. sulfanilamide

sulfanilamide

The antimicrobial drugs with the broadest spectrum of activity are A. aminoglycosides. B. macrolides. C. penicillin G. D. chloramphenicol. E. tetracyclines

tetracyclines

Which is identical in all penicillins? A) the side chain B) the beta-lactam ring

the beta-lactam ring

In which test is a zone of inhibition measured? A) the broth dilution test B) the disk-diffusion test

the disk-diffusion test In this test, zones of inhibition around disks impregnated with the drug are measured.

An antimicrobial agent should meet all of the following criteria EXCEPT A. selective toxicity B. the production of hypersensitivities C. a narrow spectrum of activity D. no production of drug resistance E. none of the above

the production of hypersensitivities

Protozoan and helminthic diseases are difficult to treat because A. they have more genes than bacteria. B. their cells are structurally and functionally similar to human cells. C. they replicate inside human cells. D. they do not have ribosomes. E. they do not reproduce

their cells are structurally and functionally similar to human cells

The larger the _______, the better the chemotherapeutic agent. A) therapeutic index B) toxic dose C) therapeutic dose D) selective toxicity E) spectrum

therapeutic index

Rifampin blocks RNA polymerase and therefore inhibits __________. A. DNA synthesis B. cell wall synthesis C. transcription D. translation

transcription

Clindamycin binds to the 50S ribosomal subunit to inhibit translocation. This antibiotic stops __________. A. transcription in eukaryotes B. transcription in prokaryotes C. DNA synthesis in eukaryotes D. translation in prokaryotes

translation in prokaryotes

Clindamycin binds to the 50S ribosomal subunit to inhibit translocation. This antibiotic stops: A. translation in prokaryotes. B. transcription in eukaryotes. C. translation in eukaryotes. D. transcription in prokaryotes

translation in prokaryotes

True/False A chemical that is bactericidal means it kills bacteria

true

True/False The lowest concentration of a drug that prevents growth is the MIC

true

A nucleoside analog used to treat HIV infection is ________. A. praziquantel B. acyclovir C. zidovudine D. amantidine E. ribavirin

zidovudine