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10 Cards in this Set
- Front
- Back
- 3rd side (hint)
moist heat |
denatures proteins. relatively fast, reliable, safe, and inexpensive. |
widely used. |
|
boiling |
destroys most microorganisms and viruses except for endospores |
treats drinking water. |
|
pressurized steam (autoclaving) |
typical treatment: 121*C/15psi for 15 min or longer, destroys endospores |
sterilizes microbiological media, laboratory glassware, surgical instruments, and other items steam can penetrate. |
|
incineration |
burns cell components to ashes |
flaming of wire inoculating loops. also used to destroy medical wastes and contaminated animal carcasses. |
|
dry heat ovens |
destroys cell components and denatures proteins. less efficient than moist heat, requiring longer times and higher temperatures. |
laboratory glassware is sterilized by heating at 160*C to 170*c for 2-3 hours. powders, oils, and other dry materials are also sterilized in ovens. |
|
filtration of fluids |
various pore sizes are available; 0.2 micrometers is commonly used to remove bacteria |
used for beer and wine, and to sterilize some heat-sensitive medications |
|
filtration of air |
HEPA filters are used to remove microbes that have a diameter of 0.3 micrometers or greater |
used in biological safety cabinets, specialized hospital rooms, and airplanes. also used in some vacuum cleaners and home air purification units. |
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ionizing radiation |
destroys DNA and possibly damages cytoplasmic membranes. produces reactive molecules that damage other cell components. items can be sterilized even after packaging. |
used to sterilize heat-sensitive materials including medical equipment, disposable surgical supplies, and drugs (penicillin). also used to destroy microbes in spices, herbs, and approved types of produce and meats. |
|
UV radiation |
damages DNA. penetrates poorly. |
used to destroy microbes in the air and drinking water, and to disinfect surfaces. |
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high pressure |
treatments of 130,000 psi are thought to denature proteins and alter the permeability of the cell. products retain color and flavor. |
used to extend the shelf life of certain commercial food products such as guacamole. |