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53 terms

7 Microbiology Unit 2 Test

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sterilization
destruction of all forms of microbial life including spores
disinfection
destruction of vegetative pathogens
antisepsis
destruction of vegetative pathogens on living tissues
sanitization
lowering of microbial counts to meet public health standards
degerming
physical removal of microbes from skin
biocide
agent which kills microorganisms
bacteriostasis
inhibition of microbial growth
asespsis
the absence of seriouse contamination
microbial death
permanent loss of reproductive capabilities
denaturation of enzymes and nucleic acids; alteration of membrane permeability.
The 2 Basic Mechanisms of physical and chemical control are the _____ & _____.
Thermal Death Point
lowest temperature at which all cells in a cultue are killed.
Thermal Death Time
Time during which all cells in a culture are killed
Decimal Reduction TIme
Time it takes to ill 90% of microorganisms in a culture
Moist Heat
Physical Control Method in which water helps break H bonds
Boiling
Physical control method using water at 100 degrees
boiling
Examples of which physical control method: baby bottles, home canning
autoclave
Physical control method using heat under pressure to raise temper of boiling
Autoclave
Examples of which physical control method: culture media, disposal of used plates, instruments, glassware
Pasteurization
Physical control method using moist heat to control only pathogens
Pasteurization
Examples of which physical control method: dairy products and juices
Incineration
Physical control method which oxidizes microorganisms
incineration
Examples of which physical control method: flaming the loop, disposables, contaminated bodies and carcasses
Hot air oven
Flow of hot air over the load 170 degrees for about an hour depending on load size
Hot air oven
Examples of which physical control method: glassware, pipettes, canisters of ointment or powder
Filtration
Physically and elctrostatically trapping microorganisms in or on a filter
Filtration
Physical control method used to reduce numbers in liquids that are heat sensitive (sera, vaccines, vitamin solutions, toxins, beers)
low temperature
Slow metabolism down to prevent infiltration
Desiccation
removal of cellular water
Desiccation
Example of which physical control method: dried food (beef jerkey)
Lyophilization
freeze drying
Osmotic Pressure
Use of sugar or salt to reduce cellular water
Osmotic pressure
Examples of which physical control method: jams and jellies, salting of meat
Radiation
Damages genetic material
Ionizing radiation
X ray or gamma ray breaks sugar phosphate backbone of DNA by generation of highly reactive hydroxyl radicals
Ionizing radiation
Examples of which physical control method: Plastics, sutures, food irradiation
Nonionizing radiation
UV radiation formation of thymine dimers
Nonionizing radiation
Used in hospitals--labs nurseries meat lockers and food processing
Microwaves
damages by heat effect
Sonication
Use of high frequency sound waves to disrupt mo's
sonication
Used in dental offices to clean tools also to remove plaque from teeth
Phenol
First agent of control; toxic to humans; used in industrial applications; decontamination of sputum and fecal samples; chloraseptic mouthwash
Phenolics
Chemically related to phenol but less toxic; Cresol--methyl phenol--add to detergent and get lysol good environment disinfectant; Creosote--wood preservative
Bisphenols
Antisceptics; Hexachloaphene--very effective against Staph infections in the past widely used but now rx; Hexyresorcinol-in mouthwash and throat losenges--will loosen mo's from mucus membrane surfaces; Triclosan--antibacterial soaps
Halogens
Chlorine--oxidizing agent, effective against bacterial endospores, gas bubbles in pool water; Iodine--antiseptic
Iodophores
Mix of iodine and detergent used in surgical scrubs etc.--Betadine, Wescodyne, loprep
Alcohols
Methanol, ethanol, propanol; 70% more effective than pure; used for topical antiseptic for cuts etc.; food preservative
Heavy Metals
Denaturate Enzymes; Copper--algicide; Mercury-- as topical antiseptic; Silver--as silver nitrate
Quaternary ammonium compounds
Super detergents; Economical; broad spectrum; non toxic; antiseptic as well as disinfectant; used in commercial antibacterial soaps
Food preservatives
Sulfur dioxide--used in wine making; Organic acids (Sorbic acid, Calcium proprionate, sodium nitrate and nitrite)
Antibiotics
Nisid--added to cheese; Natamycin--antifungal in cheese
Aldehydes
Sporocidal; Formaldehyde, Gluteraldehyde
Ethylene Oxide
True chemical sterilant; gas highly explosice; used in pressurized chamber--cold autoclave; used on plastics, spices
Peroxygens
Oxidizing agents; Ozone; Hydrogen peroxide; benzoyle peroxide; paracetic acid