Ch 8 Flashcards
sterilization
ALL living cells, spores, and acellular entities are destroyed or removed from an object
disinfection
killing/inhibition/removal of disease-causing microorganisms
what’s the difference between sterilization and disinfection?
disinfection may leave behind spores or few organisms
sanitization
reduction of microbial population to safe levels
antisepsis
destruction of microbes on living tissue
chemotherapy
application of chemicals to kill microorganisms
T/F: microorganisms are killed instantly when exposed to lethal agent
false, death is exponential. not immediate
Decimal reduction time: time required to kill __% of microorganisms
90
D value represents time/temperature
time (required to drop by 10-fold)
Z value represents time/temperature
Temp (change that decreases the microbial population by 90%)
Filtration is used for ____-sensitive and _____ microorganisms
heat-sensitive and airborne
Membrane filters are used for gaseous/liquid filtration
liquid
Destroys viruses/fungi/bacteria by degrading nucleic
acids, denaturing proteins, and disrupting cell membranes
moist heat
boiling will not destroy ____ and does not ____
endospores, sterilize
Autoclaves use ____ sterilization
steam
Pasteurization does not sterilize, but does kill ____ and slows _____
pathogens, spoilage
What is the difference between autoclave and tyndallization
Tyndallization is meant for materials that cannot withstand high temperatures
T/F: tyndallization uses intermittent sterilization
true. 30-60 minutes of steam with break periods of 23/24 hours over 2/3 cycles
Dry/Moise heat sterilization is less effective, requiring higher temps and longer exposure times
dry
what is an advantage of dry heat sterilization
does not corrode glass or metal
causes thymine dimers which prevent replication and transcription
UV radiation
