Microbiology 250 Exam 3 questions with answers

Microbiology 250 Exam 3 questions with \| \| \| \| \| \|




answers


Which of the following is true about disinfection?
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A)Bacterial endospores may not be killed on an object
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B)Fungal spores may not be killed on an object
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C)Disinfection reduces the number of pathogenic organisms on or in an object
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D)Disinfection helps reduce the threat of disease \| \| \| \| \| \|




E)All of these choices - CORRECT ANSWERS ✔✔E)All of these choices
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What is the difference between a disinfectant and an antiseptic?
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A)Disinfectants are typically applied to living tissue and antiseptics are
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typically applied to inanimate objects
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B)Disinfectants are typically applied to inanimate objects and antiseptics are
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typically applied to living tissue
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C)Disinfectants sterilize an object, whereas an antiseptic does not
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D)Antiseptics sterilize and object whereas a disinfectant does not
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E)There is no difference between a disinfectant and an antiseptic - CORRECT
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ANSWERS ✔✔B)Disinfectants are typically applied to inanimate objects and
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antiseptics are typically applied to living tissue
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,It is reported that antimicrobial agent X has a 40% death rate per minute. If
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there are 1000 organisms present in the environment when agent X is applied,
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how many organisms will remain in the environment after 5 minutes?
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A)600

B)360

C)130

D)78

E)0 - CORRECT ANSWERS ✔✔D)78
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If it was reported that Lysol had a phenol coefficient of 5.0, this would mean
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that:

A)Lysol was less effective than phenol \| \| \| \| \|




B)Lysol was equally as effective as phenol\| \| \| \| \| \|




C)Lysol was more effective than phenol \| \| \| \| \|




D)All of these choices \| \| \|




E)It is impossible to compare Lysol and phenol because they have different
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methods of action - CORRECT ANSWERS ✔✔C)Lysol was more effective
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than phenol \|




Why can liquid dish soap be used as an antimicrobial agent, even if it is not
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labeled as being antibacterial? \| \| \|




A)It denatures proteins via hydrolysis reactions
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B)It is a surfactant and dissolves lipids
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C)It is a mutagen and damages bacterial DNA
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D)It is radioactive and causes RNA damage
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,E)None of these choices - CORRECT ANSWERS ✔✔B)It is a surfactant and
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dissolves lipids \|




Why is phenol considered a good antimicrobial agent?
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A)Phenol works well in the presence of organic materials
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B)Phenol cannot damage tissue \| \| \|




C)Phenol has a pleasant odor \| \| \| \|




D)Phenol is used to kill gonococci \| \| \| \| \|




E)All of these choices - CORRECT ANSWERS ✔✔A)Phenol works well in the
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presence of organic materials \| \| \|




Sanitation:

A)Kills microorganisms via ionizing radiation
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B)Kills microorganisms via sound waves
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C)Inhibits the growth of microorganisms via ionizing radiation
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D)Inhibits the growth of microorganisms via visible light
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E)None of these choices - CORRECT ANSWERS ✔✔B)Kills microorganisms
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via sound waves
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Which form of radiation would be most effective at killing microorganisms?
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A)Infrared Light \|




B)UV light \|




C)Gamma Rays \|




D)Visible Light \|

, E)X-rays - CORRECT ANSWERS ✔✔C)Gamma Rays
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An agent that inhibits the growth of bacteria is called a/an:
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A)antiseptic

B)bactericide

C)bacteriostatic agent \|




D)sanitizer - CORRECT ANSWERS ✔✔C)bacteriostatic agent
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What is the most susceptible phase of growth for most microorganisms by an
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antimicrobial agent? \| \|




A)lag phase
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B)log phase
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C)stationary phase \|




D)death phase - CORRECT ANSWERS ✔✔B)log phase
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Which is not used to measure the effectiveness of an antimicrobial agent?
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A)Filter paper method \| \|




B)Phenol coefficient method \| \|




C)Use-dilution method \|




D)Plate count method - CORRECT ANSWERS ✔✔D)Plate count method
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When an antimicrobial agent permanently denatures proteins thus preventing
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renaturation to their native states it is considered: \| \| \| \| \| \| \|




A)bacteriostatic \|