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61 Cards in this Set
- Front
- Back
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1. A compound synthesized by bacteria or fungi that destroys or
inhibits the growth of other microbes is a/an a. synthetic drug b. antibiotic c. antimicrobial drug d. competitive inhibitor |
b. antibiotic
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What was the first disease to be treated with a specific chemical?
Tuberculosis Syphilis Bacterial meningitis Whooping cough Scarlet fever |
Syphilis
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2. Which statement is
not an aim in the use of drugs in antimicrobial chemotherapy? The drug should a. have selective toxicity b. be active even in high dilutions c. be broken down and excreted rapidly d. be microbicidal |
c. be broken down and excreted rapidly
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Antibiotics
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A chemical substance from one microorganism that can inhibit or kill another microbe even in minute amounts.
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3. Microbial resistance to drugs is acquired through
a. conjugation b. transformation c. transduction d. all of these |
d. all of these
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The golden age of antibiotics began in 1928 with Sir Alexander Fleming's discovery of an antibacterial compound he called what?
Arsenic Salvarsan Sulfonamide Penicillin Tetracycline |
Penicillin
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4. R factors are that contain a code for .
a. genes, replication b. plasmids, drug resistance c. transposons, interferon d. plasmids, conjugation |
b. plasmids, drug resistance
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Broad spectrum
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A word to denote drugs that affect many different types of bacteria, both grampositive and gram-negative.
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5. When a patient’s immune system becomes reactive to a drug, this is
an example of a. superinfection b. drug resistance c. allergy d. toxicity |
c. allergy
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Which of the following statements does not characterize the ideal antimicrobial drug?
Microbistatic Selectively toxic Safely and easily broken down and excreted by the body Remain active in the body as long as is needed Not excessively costly |
Microbistatic
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6.
An antibiotic that disrupts the normal flora can cause a. the teeth to turn brown b. aplastic anemia c. a superinfection d. hepatotoxicity |
c. a superinfection
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Narrow spectrum
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Deotes drugs that are selective and limited in their effects. For example, they iinhibit either gram-negative or gram-positive bacteria, but not both.
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7. Most antihelminthic drugs function by
a. weakening the worms so they can be flushed out by the intestine b. inhibiting worm metabolism c. blocking the absorption of nutrients d. inhibiting egg production e. all of the above |
b. inhibiting worm metabolism
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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?
Chemotherapeutic drugs Prophylactic drugs Semisynthetic drugs Synthetic drugs Antibiotics |
Antibiotics
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8. Select a drug or drugs that can prevent a viral nucleic acid from
being replicated. a. azidothymidine b. acyclovir c. amantadine d. both a and b |
d. both a and b
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Selectively toxic
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Property of an antimicrobic agent to be highly toxic against its target microbe while being far less toxic to other cells, particularly those of the host organism.
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9. Which of the following effects do antiviral drugs
not have? a. killing extracellular viruses b. stopping virus synthesis c. inhibiting virus maturation d. blocking virus receptors |
a. killing extracellular viruses
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Microbes that produce antimicrobial chemicals that inhibit the growth of other microorganisms in the same habitat are exhibiting what type of behavior?
Synergism Mutualism Antagonism Parasitism Commensalism |
Antagonism
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10. Which of the following modes of action would be most selectively
toxic? a. interrupting ribosomal function b. dissolving the cell membrane c. preventing cell wall synthesis d. inhibiting DNA replication |
c. preventing cell wall synthesis
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Prophylactic
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Any device, method, or substance used to prevent disease.
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11. The MIC is the of a drug that is required to inhibit growth of a microbe.
a. largest oncentration b. standard dose c. smallest concentration d. lowest dilution |
c. smallest concentration
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Which of the following is not a category of antimicrobial drugs?
Those that inhibit cell wall synthesis Those that inhibit DNA and RNA structure and function Those that inhibit protein synthesis Those that interfere with cell membrane structure and function Those that inhibit mRNA processing in the nucleus |
Those that inhibit mRNA processing in the nucleus
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12. An antimicrobial drug with a therapeutic index is a better
choice than one with a therapeutic index. a. low, high b. high, low |
b. high, low
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Penicillins
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A large group of naturally occurring and synthetic antibiotics produced by Penicillium mold and active against the cell wall of bacteria
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13. Matching. Select the mode of action for each drug in the left column; all but one choice is used.
sulfonamides penicillin tetracycline erythromycin quinolone amantidine polymixin a. reverse transcriptase inhibitor b. blocks the attachment of tRNA on the ribosome c. interferes with fusion of virus and host cell d. interferes with synthesis of folic acid e. breaks down cell membrane integrity f. prevents the ribosome from translocating g. blocks synthesis of peptidoglycan h. inhibition of DNA gyrase |
13. d, g, b, f, h, c, e
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Drugs that affect the bacterial cell wall are active only against what type of cells?
Gram negative Dormant Young, actively growing Endospore-forming Gram variable |
Young, actively growing
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Beta-lactamase
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An enzyme secreted by certain bacteria that cleaves the beta-lactam ring of penicilin and cephalosporin and thus provides for resistance against the antibiotic. See penicillinase.
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How are drugs that block the synthesis of folic acid able to maintain selective toxicity?
Humans do not need folic acid while bacteria do Bacteria must synthesize folic acid, while humans acquire it from their diet Eucaryotic enzymes involved in folic acid synthesis differ from the prokaryotic enzymes involved in folic acid synthesis Eucaryotic cells do not transport this class of antibiotics into the cytoplasm, while prokaryotes do Such metabolic analogs only recognize prokaryotic enzymes involved in the synthesis of folic acid |
Bacteria must synthesize folic acid, while humans acquire it from their diet
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Cephalosporins
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A group of broad-spectrumk antibiotics isolated from the fungus Cephalosporium
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Antimicrobials that block nucleic acid synthesis may act in all but which of the following manners?
They can cross-link the DNA and prevent DNA replication They can inhibit DNA helicases and prevent unwinding They can block DNA transcription They can block the synthesis of DNA and RNA nucleotides They can inhibit the action of tRNA |
They can inhibit the action of tRNA
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Polymyxin
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A mixture of antibiotic polypeptides from Bacillus polymyxa that are particularly effective against gram-negative bacteria
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Which of the categories of antimicrobial drugs exhibits the least degree of selective toxicity?
Those that disrupt cell membrane function Those that affect the cell wall Those that inhibit nucleic acid function Those that inhibit protein synthesis Those that inhibit nucleic acid synthesis |
Those that disrupt cell membrane function
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Aminoglycosides
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A complex group of drugs derived from soil actinomycetes that impairs ribosome function and has antibiotic potential. Example: streptomycin
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What portion of penicillins is responsible for differences in each compounds activity?
The peptidoglycan The thiazolidine ring The beta-lactam ring The variable side chain The carboxyl group |
The variable side chain
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Tetracyclines
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A group of broad-spectrum antibiotics with a complex 4-ring structure.
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Which of the following statements does not characterize penicillin and its relatives?
It is economical to obtain natural penicillin through microbial fermentatoin. The specifically target bacterial cell walls, so they are selectively toxic. They can induce an allergic response in some individuals. Some bacteria inactivate this drug by producing clavulanic acid. Semisynthetic penicillins have increased spectrums. |
Some bacteria inactivate this drug by producing clavulanic acid.
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Sulfonamides
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Antimicrobial drugs that interfere with the essential metabolic process of bacteria and some fungi. Also known as sulfa drugs.
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Which of the following is untrue of the cephalosporin group of drugs?
Their structure is similar to that of the penicillins. Their spectrum of activity is extremely narrow. There are four generations of these drugs. They cause fewer allergic reactions than the penicillins. They have two possible sites for placement of variable side chains. |
Their spectrum of activity is extremely narrow.
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Metabolic analogs
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Enzyme that mimics the natural substrate of an enzyme and vies for its active site.
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Aminoglycoside drugs are products of what group of microorganisms?
Soil actinomycetes Aerobic, Gram positive cocci Penicillium chrysogenum Cephalosporium acrimonium Bacillus subtilis |
Soil actinomycetes
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Competitively inhibiting
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Contorl process that relies on the ability of metabolic analogs to control microbial growth by successfully competing with a necessary enzyme to halt the growth of bacterial cells.
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What microorganism has the distinction of being one of nature's most prolific antibiotic producers?
Penicillium chrysogenum Bacillus subtilis Streptomyces sp. Cephalosporium acrimonium Micromonospora sp. |
Streptomyces sp.
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Azoles
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Five-membered heterocyclic compounds typical of histidine, which are used in antifungal therapy.
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Which antibacterial drug does not inhibit protein synthesis?
Aminoglycoside Tetracycline Penicillin Chloramphenicol Erythromycin |
Penicillin
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Acyclovir
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A synthetic purine analog that blocks DNA synthesis in certain viruses, particularly the herpes simplex viruses.
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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?
Sulfonamides Chloramphenicol Vancomycin Fluoroquinolones Oxazolidinones |
Oxazolidinones
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Resistance factors
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Plasmids, typically shared among bacteria by conjugation, that provide resistance to the effects of antibiotics.
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What was the drug used to treat individuals exposed to Bacillus anthracis endospores in 2001?
Amphotericin B Sulfonamides Methicillin Ciprofloxacin Isoniazid |
Ciprofloxacin
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Acyclovir
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A synthetic purine analog that blocks DNA synthesis in certain viruses, particularly the herpes simplex viruses.
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Why do fungal infections present special problems in terms of treatment?
Because fungi have cell walls composed of cellulose or chitin Because both fungi and humans are eukaryotes Because fungi do not have an outer membrane Because fungi are encapsulated Because fungi do not have a nucleus |
Because both fungi and humans are eukaryotes
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Probiotic
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A microbe or mixture of microbes that may be used to balance the normal flora and prevent infections.
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Why are viral infections especially difficult to treat?
Because they rely upon their host cells for the majority of their metabolic functions Because they can have RNA as their nucleic acid Because some viruses are naked while others are enveloped Because there are many types of viral structures 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
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Resistance factors
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Plasmids, typically shared among bacteria by conjugation, that provide resistance to the effects of antibiotics.
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Antiviral compounds can have all but which of the following modes of action?
Prevention of complete viral penetration of host cells Blockage of viral mRNA transcription Destruction of extracellular viruses Blockage of viral mRNA translation Prevention of viral maturation |
Destruction of extracellular viruses
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Minimum inhibitory concentration (MIC)
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The smallest concentration of drug needed to visibly control microbial growth.
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What is a logical antiviral drug target in retroviruses?
Thymidine kinase Reverse transcriptase DNA nucleotides RNA nucleotides Sterols in the cell wall |
Reverse transcriptase
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Probiotic
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A microbe or mixture of microbes that may be used to balance the normal flora and prevent infections.
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Which of the following is not a specific mechanism by which organisms genetically resist drugs?
Transfer of R factors Synthesis of enzymes that inactivate the drug Decrease in drug uptake and drug permeability into the cell Change in the number or affinity of drug receptor sites Modification of an essential metabolic pathway |
Transfer of R factors
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Minimum inhibitory concentration (MIC)
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The smallest concentration of drug needed to visibly control microbial growth.
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Strategies for combating drug resistance include all but which practice?
Responsible and appropriate drug therapy prescribed by medical personnel Limitation of non-medical uses of antibiotics in humans Responsible use of drugs by patients Restrictions on the use of antibiotics in animal feeds Distribution of free prescription drugs to underdeveloped countries |
Distribution of free prescription drugs to underdeveloped countries
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The greatest number of antimicrobic allergies is reported for what drug?
Sulfonamides Tetracycline Quinolones Penicillins Pyrantel |
Penicillins
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