front 1 At what time was pasteurization of dairy products widely used? | back 1 1895 |
front 2 Which of the following disease outbreaks can be controlled by making sure there is clean water and food? | back 2 cholera |
front 3 The time necessary to kill a population of microbes at a given temperature is called the | back 3 thermal death time. |
front 4 A fluid that has been sterilized may still contain | back 4 bacterial toxins. |
front 5 Which one of the following is the most rapid method for achieving sterilization? | back 5 Direct flame method |
front 6 Of the following, the most efficient method for sterilization of a bacteriological transfer loop is | back 6 the direct flame. |
front 7 The minimal temperature at which a microbial species dies in a given time is called the | back 7 thermal death point |
front 8 A period of two hours at 160° C is required for the destruction of endospores | back 8 in the hot air oven. |
front 9 The hot air method of sterilization is useful for those items that | back 9 are dry or do not mix with water. |
front 10 Bacterial endospores must be exposed for a period of over 2 hours for destruction with | back 10 the hot air oven. |
front 11 Moist heat kills microorganisms by | back 11 denaturation. |
front 12 If boiling water is used to destroy microorganisms, it is imperative that | back 12 traces of organic matter be removed. |
front 13 In an autoclave under 15 lb/in2 steam pressure, the approximate temperature will be _______. | back 13 121.5° C |
front 14 One of the limitations of the autoclave is that | back 14 some plasticware melts in the high heat. |
front 15 Which one of the following could not be sterilized by the autoclave? | back 15 A laboratory table |
front 16 Using a prevacuum stage in the autoclaving process can effectively | back 16 reduce the time to achieve sterilization. |
front 17 Sterilization by fractional sterilization requires | back 17 a period of three days. |
front 18 A substance that has been pasteurized | back 18 is not considered sterile. |
front 19 The conditions necessary to kill Mycobacterium tuberculosis by pasteurization are | back 19 30 min at 62.9° C. |
front 20 When applied to wounded tissue, hydrogen peroxide | back 20 releases oxygen gas. |
front 21 Formalin may be used for all the following purposes except | back 21 purifying of drinking water. |
front 22 The chemical counterpart of the autoclave uses | back 22 ethylene oxide with an inert gas. |
front 23 Detergents display their antimicrobial ability by | back 23 inducing leakage through the cell membrane. |
front 24 An advantage of the membrane filter is that | back 24 bacteria multiply and form colonies on its surface. |
front 25 HEPA filters are used to filter which one of the following? | back 25 Air |
front 26 The principle effect of ultraviolet light on bacterial cells takes place | back 26 in the DNA of the cell. |
front 27 One drawback to the use of ultraviolet light as a sterilizing agent is its failure to | back 27 penetrate liquids or solids. |
front 28 Ultraviolet light is valuable for reducing the microbial population in | back 28 the air of a hospital room. |
front 29 For UV light to kill microorganisms | back 29 direct exposure must take place. |
front 30 Energy wavelengths near 265 nm are most destructive when one is using | back 30 ultraviolet light. |
front 31 Radiations with wavelengths between 400 nm and 800 nm are considered | back 31 visible light. |
front 32 In the microwave oven, the energy of microwaves is converted to | back 32 the heat of friction. |
front 33 When food has been salted | back 33 water diffuses out of microorganisms causing them to shrivel. |
front 34 Low temperature is | back 34 bacteriostatic. |
front 35 A method of preserving food that depends upon osmosis is | back 35 treating the food with high concentrations of sugar. |
front 36 The halogen common to Wescodyne®, Betadine®, and Ioprep® | back 36 iodine in a form known as iodophor. |
front 37 Which one of the following elements would be classified as a halogen? | back 37 Chlorine |
front 38 Iodophors are | back 38 complexes of iodine and detergents that release iodine over long periods of time. |
front 39 Which one of the following statements does not apply to phenol? | back 39 It has a low cost, a sweet odor, and no effects on the skin. |
front 40 Chlorhexidine is a phenol derivative used to | back 40 wash hands and clean wounds superficially. |
front 41 Triclosan destroys bacteria by | back 41 disrupting cell membranes. |
front 42 Copper has its principle activity against | back 42 organisms that contain chlorophyll. |
front 43 Silver nitrate may be used to | back 43 prevent gonorrhea in the eyes of newborns. |
front 44 Mercury is rarely used in antiseptics in the modern era because | back 44 mercury is very toxic to body tissues. |
front 45 Heavy metals generally kill microorganisms by | back 45 reacting with proteins and binding them together. |
front 46 At a concentration of 70 percent, ethyl alcohol has virtually no effect on | back 46 bacterial spores. |
front 47 Before alcohol is used for disinfection purposes | back 47 the object to be treated must be carefully cleaned. |
front 48 destroys bacterial endospores with heat in about 15 minutes. | back 48 The autoclave |
front 49 also is known as tyndallization. | back 49 Fractional sterilization |
front 50 oxidizes proteins and creates an arid environment. | back 50 The hot air oven |
front 51 is electromagnetic energy with a wavelength between 100 and 400 nm. | back 51 Ultraviolet (UV) light |
front 52 uses pressurized steam at 121°C. | back 52 The autoclave |
front 53 causes linkage of adjacent thymine molecules on DNA. | back 53 Ultraviolet (UV) light |
front 54 employs 30 minutes of steam on three successive days. | back 54 Fractional sterilization |
front 55 requires a two-hour exposure for the destruction of bacterial endospores. | back 55 The hot air oven |
front 56 uses free-flowing steam at 100°C. | back 56 Fractional sterilization |
front 57 interferes with replication of the bacterial chromosomes. | back 57 Ultraviolet (UV) light |
front 58 can be used to sterilize an environmental surface. | back 58 Ultraviolet (UV) light |
front 59 is the most dependable method for the destruction of endospores. | back 59 The autoclave |
front 60 uses dry heat used for sterilization. | back 60 The hot air oven |
front 61 will melt plasticware in the pressurized steam. | back 61 The autoclave |
front 62 is a heat-free method of sterilization. | back 62 Ultraviolet (UV) light |
front 63 sharp instruments often become dull during this procedure. | back 63 The autoclave |
front 64 is useful for water-free oily substances and dry powders. | back 64 The hot air oven |
front 65 can have a prevacuum stage to increase the efficiency of sterilization. | back 65 The autoclave |
front 66 can reduce airborne contamination effectively. | back 66 Ultraviolet (UV) light |
front 67 has effects on microorganisms equivalent to that of baking | back 67 The hot air oven |
front 68 Ultraviolet light | back 68 Radiation at 265 nm that is absorbed by DNA |
front 69 Pasteurization | back 69 Heating liquids to 62.9°C for 30 minutes |
front 70 Osmosis | back 70 Water movement across a membrane toward the area where water concentration is lower |
front 71 Thermal death time | back 71 Time required to kill an organism at a specific temperature |
front 72 Autoclave | back 72 Chamber for steam sterilizing at 121°C |
front 73 Membrane filter | back 73 Cellulose acetate pad through which fluids, but not cells, pass |
front 74 Sterilization | back 74 Process that kills all living organisms and spores |
front 75 Thermal death point | back 75 Minimal temperature at which an organism dies in a given time period |
front 76 Sanitization | back 76 Microbiostatic and microbial populations have been reduced or where their growth has been inhibited |
front 77 denaturation | back 77 change in the chemical or physical property of a protein. |
front 78 Incineration | back 78 using a direct flame can kill microbes very rapidly |
front 79 <p>Thermal death time</p> <br> | back 79 the time necessary for killing the population at a given temperature |
front 80 Thermal death point | back 80 minimal temperature at which it dies in a given time |
front 81 Filtration | back 81 mechanical method used to remove microorganisms from a solution, organisms are trapped in the pores of the filter |
front 82 Sterilization | back 82 microbicidal and the destruction of all living microbes, including spores and viruses, on an object or in an area |
front 83 Pasteurization | back 83 reduces the bacterial population of a liquid such as milk and destroys organisms that may cause spoilage and human disease |
front 84 autoclave | back 84 Moist heat in the form of pressurized steam is regarded as the most dependable method for sterilization |
front 85 prevacuum autoclave | back 85 draws air out of the sterilizing chamber at the beginning of the cycle. |