micro ch. 7

Oxidizing agents include all of the following EXCEPT A) chlorine. B) iodine. C) hydrogen peroxide. D) glutaraldehyde. E) ozone.

glutaraldehyde.

The antimicrobial activity of chlorine is due to which of the following? A) the formation of HYPOCHLOROUS acid B) the formation of ozone C) disruption of the plasma membrane D) the formation of hydrochloric acid E) the formation of a hypochlorite ion

the formation of HYPOCHLOROUS acid

Which of the following is a limitation of the autoclave? A) It cannot be used with heat-labile materials. B) It requires an excessively long time to achieve sterilization. C) It cannot inactivate viruses. D) It cannot kill endospores. E) It cannot be used with glassware.

It cannot be used with heat-labile materials.

Which of the following regarding antimicrobial control agents is FALSE? A) Contaminating organic debris such as blood or sputum decrease effectiveness. B) Some agents inactivate viruses by attacking cell membrane lipids. C) Some agents kill by denaturing microbial cell proteins. D) Silver is used for treating antibiotic-resistant bacteria. E) Some agents affect microbial cell membranes by dissolving lipids.

Some agents inactivate viruses by attacking cell membrane lipids.

Which of the following best describes the pattern of microbial death? A) All the cells in a culture die at once. B) The pattern varies depending on the antimicrobial agent. C) Not all of the cells in a culture are killed. D) The cells in a population die at a constant rate. E) The pattern varies depending on the species.

The cells in a population die at a constant rate.

All of the following substances are effective against nonenveloped viruses EXCEPT A) chlorine. B) ozone. C) alcohol. D) ethylene oxide. E) None of the answers is correct; all of these are equally effective against nonenveloped viruses.

alcohol.

Which of the following pairs of terms is mismatched? A) bacteriostatic — kills vegetative bacterial cells B) germicide - kills microbes C) virucide - inactivates viruses D) fungicide — kills yeasts and molds E) sterilant — destroys all living microorganisms

bacteriostatic — kills vegetative bacterial cells

Which of the following disinfectants acts by disrupting the plasma membrane? A) bisphenols B) soaps C) halogens D) aldehydes E) heavy metals

bisphenols

Which of the following substances is used for surgical hand scrubs? A) chlorine bleach B) soap C) chlorhexidine D) phenol E) glutaraldehyde

chlorhexidine

Application of heat to living cells can result in all of the following EXCEPT A) breaking of hydrogen bonds. B) denaturation of enzymes. C) decreased thermal death time. D) damage to nucleic acids. E) alteration of membrane permeability

decreased thermal death time.

An agent used to reduce the number of bacteria on a toilet would most accurately be called a(n) A) virucide. B) antiseptic. C) disinfectant. D) aseptic. E) fungicide.

disinfectant.

Which of the following chemical agents is used for sterilization? A) chlorine B) ethylene oxide C) soap D) alcohol E) phenolics

ethylene oxide

Which of the following is the best method to sterilize heat-labile solutions? A) pasteurization B) membrane filtration C) freezing D) autoclave E) dry heat

membrane filtration

Which of the following does NOT achieve sterilization? A) pasteurization B) ethylene oxide C) supercritical fluids D) dry heat E) autoclave

pasteurization

Disinfection of water is achieved by all of the following EXCEPT A) ozone. B) peracetic acid. C) copper sulfate. D) UV radiation. E) chlorine.

peracetic acid.