22.  Media containing spores and thermolabile constituents are sterilized by
A.pasteurization
B.UV radiation
C.dry heat
D.tyndalization

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23. A(n)____is used to prevent infection by killing or inhibiting pathogen growth on animal tissues.
A.bacteriostatic agent
B.sanitizer
C.disinfectant
D.antiseptic

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24. One drawback to the use of ultraviolet light as a sterilizing agent is its
A.failure to kill bacteria
B.failure to bacterial spores
C.failure to kill microbes in a closed environment
D.failure to kill microbes located in the center of an object

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25. Ethylene oxide is used to destroy or kill which of the following microbes?
A.Bacteria
B.Spores
C.Fungi
D.All of these

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26. Which of the following was the first widely used antiseptic and disinfectant?
A.Chlorine
B.Phenol
C.Iodine
D.Alcohol

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27. If a 1:600 dilution of a test compound kills a standard population of Staphylococcus aureus in 10 minutes but not 5 minutes while a 1:60 dilution of phenol kills the population in the same time, what is the phenol coefficient of the test compound?
A.1
B.5
C.10
D.50

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28. Microbes can be removed from a liquid solution by the process of
A.filtration
B.freeze-drying
C.osmosis
D.desiccation

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