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Questions and Answers
What is microbial antagonism?
What is microbial antagonism?
the ability of the normal flora to outcompete and outgrow pathogens
What is superinfection?
What is superinfection?
Superinfection is a disease caused by an organism that is often an opportunist or one that was present in low numbers.
What causes thrush?
What causes thrush?
Candida albicans
Which of the following classifications would best describe Candida albicans?
Which of the following classifications would best describe Candida albicans?
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If the patient were to get a subsequent urinary tract infection, what should the doctor prescribe knowing that she is susceptible to thrush?
If the patient were to get a subsequent urinary tract infection, what should the doctor prescribe knowing that she is susceptible to thrush?
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Who was the most likely source of infection for this child?
Who was the most likely source of infection for this child?
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What is DOT?
What is DOT?
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Which drug for the treatment of tuberculosis inhibits RNA production and colors body secretions red-orange?
Which drug for the treatment of tuberculosis inhibits RNA production and colors body secretions red-orange?
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What is the therapeutic index?
What is the therapeutic index?
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How did the multi-drug-resistant strains of Mycobacterium tuberculosis, like those in the prison, arise?
How did the multi-drug-resistant strains of Mycobacterium tuberculosis, like those in the prison, arise?
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Match the following descriptions of cellular structures with the type of cell in which they are found.
Match the following descriptions of cellular structures with the type of cell in which they are found.
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Which among the following cell features of bacteria are potential targets for Dr. Ehrlich's 'magic bullets'?
Which among the following cell features of bacteria are potential targets for Dr. Ehrlich's 'magic bullets'?
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The ____________ is a defining characteristic of bacteria which is not found in eukaryotes.
The ____________ is a defining characteristic of bacteria which is not found in eukaryotes.
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The cytosol of bacteria contains ____________ which has components different from the structure of eukaryotes.
The cytosol of bacteria contains ____________ which has components different from the structure of eukaryotes.
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When a nurse rubs your skin with rubbing alcohol prior to administering an injection, what process(es) is he carrying out?
When a nurse rubs your skin with rubbing alcohol prior to administering an injection, what process(es) is he carrying out?
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Which of the following is NOT an important consideration when preparing to use a chemical to disinfect a diaper changing table in a public restroom?
Which of the following is NOT an important consideration when preparing to use a chemical to disinfect a diaper changing table in a public restroom?
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Many MRSA strains are sensitive to other antibiotics. Which of the following methods would be the best way to evaluate sensitivity to other antibiotics?
Many MRSA strains are sensitive to other antibiotics. Which of the following methods would be the best way to evaluate sensitivity to other antibiotics?
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In examining a MRSA strain, researchers find that degraded penicillin is found in the culture medium. What is the most likely mechanism of resistance?
In examining a MRSA strain, researchers find that degraded penicillin is found in the culture medium. What is the most likely mechanism of resistance?
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Clostridium difficile is a common healthcare-associated infection. It is often transferred between patients on the hands of health care workers. Rank the following prevention and control strategies from most beneficial (1) to least beneficial (4).
Clostridium difficile is a common healthcare-associated infection. It is often transferred between patients on the hands of health care workers. Rank the following prevention and control strategies from most beneficial (1) to least beneficial (4).
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Which antibiotic is overcome by beta-lactamases?
Which antibiotic is overcome by beta-lactamases?
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How might efflux pumps increase antibiotic resistance in bacteria?
How might efflux pumps increase antibiotic resistance in bacteria?
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Bacteria that are resistant to sulfonamide have enzymes that have a greater affinity for what?
Bacteria that are resistant to sulfonamide have enzymes that have a greater affinity for what?
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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?
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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Membrane transport proteins are required for which mode(s) of antibiotic resistance?
Membrane transport proteins are required for which mode(s) of antibiotic resistance?
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What is meant by selective toxicity?
What is meant by selective toxicity?
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Why are chemotherapeutic agents that work on the peptidoglycan cell wall of bacteria a good choice of drug?
Why are chemotherapeutic agents that work on the peptidoglycan cell wall of bacteria a good choice of drug?
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Why is polymyxin only used on the skin?
Why is polymyxin only used on the skin?
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Quinolones and fluoroquinolones act against what bacterial target?
Quinolones and fluoroquinolones act against what bacterial target?
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Why is it difficult to find good chemotherapeutic agents against viruses?
Why is it difficult to find good chemotherapeutic agents against viruses?
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The first true antibiotic was __________, which was discovered by __________.
The first true antibiotic was __________, which was discovered by __________.
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Who proposed the concept of chemotherapy, that compounds might selectively kill pathogens without harming people?
Who proposed the concept of chemotherapy, that compounds might selectively kill pathogens without harming people?
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Which of the following is a primary advantage of semisynthetic drugs?
Which of the following is a primary advantage of semisynthetic drugs?
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Which of the following antimicrobial drugs would likely be useful to treat a methicillin-resistant Staphylococcus aureus infection because it effectively blocks initiation of translation?
Which of the following antimicrobial drugs would likely be useful to treat a methicillin-resistant Staphylococcus aureus infection because it effectively blocks initiation of translation?
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Which of the following is NOT a beta-lactam antibiotic?
Which of the following is NOT a beta-lactam antibiotic?
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Which of the following is NOT a direct mode of action of antimicrobial drugs?
Which of the following is NOT a direct mode of action of antimicrobial drugs?
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Bacitracin blocks the transport of NAG and NAM across the cytoplasmic membrane to the cell wall. This would result in weak cell walls and __________.
Bacitracin blocks the transport of NAG and NAM across the cytoplasmic membrane to the cell wall. This would result in weak cell walls and __________.
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Beta-lactam antibiotics such as penicillins, have an effect on which of the following types of cells?
Beta-lactam antibiotics such as penicillins, have an effect on which of the following types of cells?
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Amoxicillin is very effective for treating infections with Gram-positive bacteria but rarely causes side effects in humans. This is an example of
Amoxicillin is very effective for treating infections with Gram-positive bacteria but rarely causes side effects in humans. This is an example of
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The first antimicrobial widely available for treatment of bacterial infections was a synthetic compound which
The first antimicrobial widely available for treatment of bacterial infections was a synthetic compound which
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Which of the following antifungals works by binding to ergosterol in membranes?
Which of the following antifungals works by binding to ergosterol in membranes?
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A drug is structurally similar to PABA and inhibits folic acid synthesis. It is most likely a(n)
A drug is structurally similar to PABA and inhibits folic acid synthesis. It is most likely a(n)
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Which of the following statements is true of selective toxicity?
Which of the following statements is true of selective toxicity?
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Antimicrobials known as 'attachment antagonists' are particularly useful for preventing
Antimicrobials known as 'attachment antagonists' are particularly useful for preventing
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The antifungals known as polyenes interact with ________, a lipid unique to fungus membranes.
The antifungals known as polyenes interact with ________, a lipid unique to fungus membranes.
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The tetracyclines interfere with
The tetracyclines interfere with
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AZT and Valaciclovir are antiviral nucleoside analogs that interfere with
AZT and Valaciclovir are antiviral nucleoside analogs that interfere with
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Polymyxin is effective against only some Gram-negative bacteria; therefore, it is considered a
Polymyxin is effective against only some Gram-negative bacteria; therefore, it is considered a
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An antimicrobial disk on a Kirby-Bauer plate that shows no zone of inhibition indicates that the microbe being tested is
An antimicrobial disk on a Kirby-Bauer plate that shows no zone of inhibition indicates that the microbe being tested is
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Put the following routes of administration in order, from the route that results in the highest concentration of drug in the bloodstream to the route that results in the lowest concentration: a. topical b. intravenous c. oral d. intramuscular
Put the following routes of administration in order, from the route that results in the highest concentration of drug in the bloodstream to the route that results in the lowest concentration: a. topical b. intravenous c. oral d. intramuscular
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Label each figure with the appropriate route of antimicrobial administration.
Label each figure with the appropriate route of antimicrobial administration.
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The drug metronidazole is effective on both bacteria and some protozoa. It can therefore be described as a
The drug metronidazole is effective on both bacteria and some protozoa. It can therefore be described as a
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Which of the following groups of drugs can become incorporated into the bones and teeth of a fetus?
Which of the following groups of drugs can become incorporated into the bones and teeth of a fetus?
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Which of the following can result when antibiotic therapy disrupts the normal microbiota?
Which of the following can result when antibiotic therapy disrupts the normal microbiota?
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The broth dilution test can provide information for determining
The broth dilution test can provide information for determining
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Infection of the ________ would be the hardest to treat with antimicrobial drugs.
Infection of the ________ would be the hardest to treat with antimicrobial drugs.
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Which of the following activities can be shown to increase resistance among microbial populations?
Which of the following activities can be shown to increase resistance among microbial populations?
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Which of the following is NOT associated with microbial mechanisms of resistance?
Which of the following is NOT associated with microbial mechanisms of resistance?
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The cooperative activity of drugs such as beta-lactam antibiotics and clavulanic acid, a β-lactamase inhibitor, is known as
The cooperative activity of drugs such as beta-lactam antibiotics and clavulanic acid, a β-lactamase inhibitor, is known as
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Some bacteria are resistant to antimicrobials due to the activity of ________, which removes many of them.
Some bacteria are resistant to antimicrobials due to the activity of ________, which removes many of them.
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It is inappropriate to prescribe antibacterial agents to treat colds or flu because
It is inappropriate to prescribe antibacterial agents to treat colds or flu because
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Why does the physician start Caleb on the antibiotic azithromycin before laboratory results come back?
Why does the physician start Caleb on the antibiotic azithromycin before laboratory results come back?
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Which of the following choices correctly matches the class of antibiotic and its mode of action?
Which of the following choices correctly matches the class of antibiotic and its mode of action?
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If Caleb's strain of M. tuberculosis is sensitive to antibiotic treatment, which of the following could be used to treat his infection?
If Caleb's strain of M. tuberculosis is sensitive to antibiotic treatment, which of the following could be used to treat his infection?
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Why does Dr. Bell start Caleb on HIV therapy in addition to the antibiotics used to treat the tuberculosis?
Why does Dr. Bell start Caleb on HIV therapy in addition to the antibiotics used to treat the tuberculosis?
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Which of the following contribute to drug resistance in M. tuberculosis?
Which of the following contribute to drug resistance in M. tuberculosis?
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Study Notes
Microbial Antagonism & Infections
- Microbial antagonism refers to the normal flora's ability to outcompete and inhibit pathogens.
- Superinfection occurs due to disease caused by opportunistic organisms that proliferate after normal flora is disrupted by antibiotics.
- Thrush, a type of superinfection, is primarily caused by Candida albicans.
- Candida albicans is classified as a yeast.
Antibiotic Prescribers & Treatment Strategies
- For recurrent urinary tract infections in patients susceptible to thrush, prescribe an antibiotic specific to the bacterial species.
- Infection sources can trace back to family contacts, highlighting the uncle as a likely source in a case scenario.
- Directly Observed Therapy (DOT) ensures adherence to treatment protocols.
Antimicrobial Therapy & Resistance
- Rifampin is an antibiotic for tuberculosis that inhibits RNA production and can color body secretions red-orange.
- Therapeutic index measures drug tolerance versus effective dose, an important consideration for antibiotic prescriptions.
- Multi-drug-resistant strains of Mycobacterium tuberculosis can arise through conjugation and plasmid-mediated resistance factor exchange.
- Membrane transport proteins are integral in mechanisms like efflux pumps and beta-lactamase production that enhance bacterial resistance.
Bacterial Characteristics & Antibiotic Targets
- Bacteria are classified into Archaea and Bacteria domains, distinguished by their structures like cell walls and ribosome types.
- Peptidoglycan in bacterial cell walls is a vital target for chemotherapy as it is absent in humans.
- The effectiveness of drugs like penicillin is compromised by enzymes like beta-lactamase, produced by resistant bacteria.
Disinfection & Infection Control
- Effective hand hygiene with soap and water is crucial in preventing healthcare-associated infections like Clostridium difficile.
- Disk diffusion is the method used to evaluate antibiotic sensitivity.
Selective Toxicity & Chemotherapeutic Strategies
- Selective toxicity is the principle where chemotherapeutic agents target pathogens without harming the host.
- Chemotherapeutics that act on peptidoglycan cell walls are favorable as humans lack these structures.
Antifungal Treatments & Mechanisms
- Antifungal agents such as amphotericin B and nystatin bind to ergosterol, unique to fungal membranes, disrupting their functionality.
- Fungal resistance can emerge, and polyenes are a class of antifungals that specifically interact with ergosterol.
Routes of Administration & Drug Efficacy
- Routes of administration impact drug concentration, ranked highest with intravenous, followed by intramuscular, oral, and topical.
- Metronidazole is a broad-spectrum drug effective against both bacteria and protozoa.
- Tetracyclines can inadvertently affect fetal development.
Mechanisms of Microbial Resistance
- Factors like antibiotic use against viral infections, incomplete treatment courses, and incorrect medication administration contribute to drug resistance.
- Efflux pumps can enhance resistance by actively removing antibiotics from bacterial cells.
Treatment Protocols for Infections
- Broad-spectrum antibiotics like azithromycin are often administered initially due to their effectiveness against various bacteria.
- Specific treatment regimens for tuberculosis can include streptomycin, isoniazid, ethambutol, and rifampin.
HIV Therapy in Conjunction with Antibiotics
- Initiating HIV therapy alongside tuberculosis treatment is crucial, as TB antibiotics do not affect the HIV virus directly.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your understanding of key concepts in microbiology with these flashcards from Chapter 10. Topics covered include microbial antagonism, superinfection, and causes of thrush. Perfect for reinforcing your learning and preparing for exams.
