Micro Bio Chp 10 Exam 4
Who proposed the concept of chemotherapy, that compounds might selectively kill pathogens without harming people?
An antimicrobial that inhibits cell wall synthesis will result in which of the following?
Cells become more susceptible to osmotic pressure
Beta-lactam antibiotics have an effect on which of the following types of cells?
Which of the following is a primary advantage of semisynthetic drugs?
they have a broader spectrum of action
Which of the following drugs specifically targets cell walls that contain arabinogalactan-mycolic acid?
Which of the following antibiotics disrupts cytoplasmic membrane function?
Which of the following is NOT a target of drugs that inhibit protein synthesis?
interference with alanine-alanine bridges
this figure represents a petri plate. the gray area is where bacteria A is growing, the black area is where bacteria B is growing. the white area is a zone where neither organism is growing. What is the best interpretation of what is observed on the plate?
Bacteria B is producing an antibiotic that inhibits the growth of bacteria A.
Which of the following type of antimicrobial agent has the narrowest spectrum of action?
The first synthetic antimicrobial widely available for treatment of infections
was an attachment antagonist
In the compound lamivudine an -SH group replaces an -OH group found in cytosine. When used as a medication it will
interfere with nucleic acid synthesis
Which of the following groups of drugs can become incorporated into the bones and teeth of the fetus?
Which of the following can result when antibiotic therapy disrupts the normal microbiota?
both pseudomembranous colitis and thrush
A compound is extracted from a microbial culture and is modified in the laboratory for use as an oral medication. this product would be a
B-lactamase production is an example of which of the following types of resistance?
inactivation of the drug
Bacillus licheniformis secretes a compound that inhibits the growth of other Gram-positive bacteria. this is an example of an
Most drugs that inhibit the synthesis of the cell wall act by
preventing the cross-linkage of NAM subunits.
Most broad spectrum antibiotics act by
inhibiting protein synthesis
Which of the following antifungals works by inhibiting ergosterol synthesis?
both fluconazole and turbinafine
A drug is structurally similar to PABA and inhibits folic acid synthesis. It is most likely a
Which of the following pathways is specifically inhibited by sulfonamides?
the conversion of PABA to dihydrofolic acid
Which of the following drugs inhibits nucleic acid synthesis in prokaryotes?
The cooperative activity of drugs such as beta-lactam antibiotics and clavulanic acid, a B-lactamase inhibitor, is known as
Alterations in the structure of which of the following are an important aspect of Gram-negative bacterial resistance to antimicrobial drugs?
it is inappropriate to prescribe antibacterial agents to treat colds or flu becasue
these diseases are caused by viruses
Who discovered the first antibiotic widely available to the general public?
Which of the following statements is true of selective toxicity?
Selective toxicity takes advantage of structural differences between host and pathogen.
Antimicrobials that block protein synthesis by binding to the mRNA are
antisense nucleic acids
The E-test determines which of the following?
both susceptibility and MIC(minimum inhibitory concentration)
The therapeutic range of an antimicrobial is the
range of concentrations at which the antimicrobial is both effective and non-toxic
Which of the following interferes with cell wall synthesis by blocking alanine bridge formation?
both cycloserine and vancomycin
Antimicrobial sugars analogs are effective for
preventing virus attachment
Which of the following is a measurement associated with the broth dilution test?
lack of turbidity
Infection of the _____ would be the hardest to treat with antimicrobial drugs.
Disruption of the normal microbiota can result in infections caused by which of the following microbes?
Candida albicans, Mycobacterium, and Clostridium difficile
The antimicrobials called quinolone act by
inhibiting DNA replication
How does resistance to drugs spread in bacterial populations?
Both horizontal gene transfer and the growth of biofilms spread drug resistance
The mechanism of action of the antibiotic vancomycin is
inhibition of cell wall synthesis
The tetracyclines interfere with
Pentamidine is an example of an antimicrobial that
binds to DNA
The mechanism of action of erythromycin is
inhibition of protein synthesis
Methicillin is an example of the beta-lactam class of drugs that
inhibits cell wall synthesis
Ribavirin is an antiviral that interferes with
nucleic acid synthesis
The antimicrobial polymyxin
disrupts cytoplasmic membranes
Drug resistant populations of microbes arise when
exposure to drugs selectively kills sensitive cells, allowing overgrowth of resistant cells.
Any drug that acts against a disease is called a (analog/ antibiotic/ chemotherapeutic) agent.
Selective (toxicity/ action/ treatment) means that a given antimicrobial agent is more toxic to a pathogen than to the host being treated.
Nucleotide or nucleoside (analogs/ antisense/ acids) are antimicrobial agents that mimic the chemical structure of DNA building blocks.
A microbe resistant to a variety of different antimicrobials is said to have (cross/ drug/ multiple) resistance.
Secondary infections that result from the killing of some of the normal microbiota are called (antagonism/ superinfection/ resistance).
Competition between beneficial microbes and potential pathogens is called (synergy/ antagonism).
A (bacteriostatic/ bacteriocidal/ minimum) concentration of a drug is one at which microbes survive but are not able to grow and reproduce.
the ratio of a medication's dose that cane tolerated to its effective dose is the therapeutic (range/ index) of the medication.
Some bacteria develop resistance to groups of drugs because the drugs are all structurally similar to each other; this is a phenomenon known as (cross/ multiple) resistance.
Second generation drugs are semisynthetic drugs developed to combat (immunity/ resistance) against an existing drug.
Drugs that slow down bacterial growth would be (competitive/ synergistic/ antagonistic) to penicillin.
External infections can be treated by (surface/ topical) administration, in which a drug is applied directly to the site of infection.
the abbreviation (MIC/ MID/ MD) stands for the smallest amount of a drug that will inhibit the growth and reproduction of a pathogen.
Antiviral medication frequently block unique (proteins/enzymes/ molecules) to prevent production of new virus.
Some medications for influenza are (attachment/ binding/ microbial) antagonists that block the ability of the virus to enter cells.