bio week 8 homework – Flashcards
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which antibiotic is overcome by beta-lactamases?
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Penicillin
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how might efflux pumps increase antibiotic resistance in bacteria?
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resistant bacteria can have more efflux pumps, and can have less specific efflux pumps
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Bacteria that are resistant to sulfonamide have enzymes that have a greater affinity for what?
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PABA
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Why would an efflux pump for penicillin located on a bacterial cell membrane NOT be effective at providing resistance to the drug?
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Penicillin disrupts the cell wall, which is located outside of the cell membrane
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membrane tansport proteins are required for which mode (s) of antibiotic resistance?
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Efflux pumps, beta-lactamases, and membrane transport proteins
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who was the most likely source of infection for this child?
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Uncle
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What is DOT?
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Directly Observed Therapy
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which drugfor the treatment of tuberculosis inhabits RNA production and colors body secretions red-orange?
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Rifampin
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What is the therapeutic index?
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the drug dose that patient can tolerate divided by the effective dose
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How did the multi-drug-resistant strains of Mycobacterium tuberculosis
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conjugation and exchange of resistance factor located on plasmids
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If a particular bacterial species is resistant to bets-lactam antibiotics, which of the following might you expect to ind inside the bacterial cells?
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R-plasmids
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which of the following is NOT associated with microbial mechanisms of resistance?
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denaturation of proteins
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which of the following is NOT a type of side effect exhibited by antimicrobial drugs? -allergic reaction -damage to live or kidney tissue -inhibition of host cellular enzymes -disruption of normal microbiota
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inhibition of host cellular enzymes
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which of the following antimicrobial drugs would likely be useful to treat staphylococcal infection?
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erythromycin
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what is meant by selective toxicity?
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Chemotherapeutic agents should ct against the pathogen and not the host
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why are chemotherapeutic agents that work on the peptidoglycan cell wall of bacteria a good choice of drug?
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Humans and other animal hosts lack peptidoglycan call walls
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Why is polymyxin only used on the skin?
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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
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Quinolones and fluoroquinolones act against what bacterial target?
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DNA gyrase
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Why is it difficult to find food chemotherapeutic agents against viruses?
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Viruses depend on the host cells machinery, so it is hard to find a viral target that would leave the host cell unaffected.
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Certain cancer cells have ABC transport molecules at the cell surface. These transporters use energy from ATP to move chemotherapeutic agents out of the cell. Which of the following do you think these transporters are most closely related to?
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membrane pumps
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A researcher creates an antibiotic that binds to a protein present only on B. anthracis (the causative agent of anthrax), lysing the cell from the outside. After a couple of years using this antibiotic, some resistant organisms are found. Which of the following best outlines the mechanism for development of this resistance?
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mutation in B. anthracis --> altered target --> resistant bacterium
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A new bacterial molecule is discovered. This molecule binds to an antibiotic and facilitates the binding of a phosphate group, thus inactivating the antibiotic. Which category best describes the mechanism of antibiotic resistance conferred by this molecule?
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bacterial enzymes
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__________ cells would be expected to be the most susceptible to the action of polyene drugs such as amphotericin B, while __________ cells would be the least susceptible.
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Fungi; bacterial
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The following molecules are involved in the biosynthetic pathway that leads to the formation of DNA and RNA; what is their correct sequence in this pathway? a. PABA b. tetrahydrofolic acid c. purine and pyrimidine nucleotides d. dihydrofolic acid
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A,D, B, C
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why is the drug actinomycin used only on research applications or in the treatment of cancer?
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because it is active against both prokaryotic and eukaryotic cells
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which of the following is NOT a direct mode of action of antimicrobial drugs?
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inhibition of flagella formation
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An antimicrobial drug that blocks the transport of NAG and NAM from the cytoplasm is targeting which of the following cellular processes?
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cell wall synthesis
