15. If a canning procedure is not properly followed, which type of microbe is most likely to grow in the canned food?
A.Obligate Aerobe
B.Acidophile
C.Mesophile
D.Obligate Anaerobe

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16. Bactericidal concentration of phenol is
A.0.25%
B.0.5%
C.0.75%
D.1%

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17. Which of the following is most effective for sterilizing mattresses and plastic petri plates?
A.Chlorine
B.Ethylene oxide
C.Glutaraldehyde
D.Ultraviolet radiation

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18. Which of the following skin disinfectant(s) is/are most frequently used?
A.Isopropyl alcohol
B.Ethyl alcohol
C.Both (a) and (b)
D.none of these

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19. All of the following are sporicidal except
A.glutaraldehyde
B.ethylene oxide
C.formaldehyde
D.alcohol

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20. Which of the following describes the effect of ionizing radiation on microbes?
A.Changes the 3-dimensional structure of proteins to a 2-dimen-sional form
B.Substantially decreases enzymatic activity, slowing microbial reproduction
C.Induces electrons and protons to jump out of the molecules of the microbe
D.None of the above

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21. The process of making an object free from living organisms including bacterial and fungal spores and viruses is known as
A.pasteurization
B.antisepsis
C.disinfection
D.sterilization

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