MICROBIO CH9 – Flashcards
Unlock all answers in this set
Unlock answersquestion
Aseptic means
answer
free of pathogens.
question
Which of the following is the most difficult to inactivate?
answer
bacterial endospores
question
Which of the following is used to sterilize items that should not, or cannot, be exposed to heat or water?
answer
ethylene oxide
question
Disinfectants that damage membranes include
answer
both alcohol and phenolics.
question
A nurse preparing a section of skin for an injection is an example of __________.
answer
degerming
question
Boiling water for 10 minutes is effective in ridding it of
answer
both growing bacteria and enveloped viruses.
question
Which of the following is the most important part of sterilization using an autoclave?
answer
increased pressure
question
It has been determined that the temperature in an autoclave should reach __________ for sterilization.
answer
121 degrees Celsius
question
What role does pressure play in an autoclave?
answer
Pressure is applied to boiling water to prevent heat from escaping as steam.
question
How do scientists ensure that autoclaved materials were actually sterilized?
answer
They may place a sterility indicator with a special dye to detect the growth of endospores.
question
What is the purpose of an autoclave?
answer
to sterilize equipment and media
question
Where are you likely to find an autoclave?
answer
in a dentist office
question
Why is autoclaving rather than boiling water used for sterilization?
answer
Boiling water does not kill everything, including bacterial endospores and some protozoan cysts.
question
Why do containers of liquid placed in an autoclave need to remain at least slightly open?
answer
If they remain closed, they may implode.
question
Why are endospores sometimes used in sterility indicators?
answer
They are the hardest life form to kill.
question
An antimicrobial chemical used on the skin is usually called a(n) __________.
answer
antiseptic
question
Hydrogen peroxide does NOT make a good antiseptic for open wounds because __________.
answer
catalase in human tissues neutralizes it
question
Which biosafety level requires that laboratory air be HEPA-filtered but is insufficient for the safe study Ebola?
answer
BSL-3
question
Damage to the cell wall will adversely affect a bacterial cell by making it more susceptible to __________.
answer
osmotic pressure
question
Which of the following infectious agents is least resistant to destruction by chemical methods?
answer
enveloped viruses
question
Which of the following statements is TRUE of disinfectants?
answer
they are used on inanimate surfaces
question
Which of the following is an example of sanitization?
answer
A public toilet is treated with disinfectants.
question
Antimicrobial agents that damage nucleic acids also affect
answer
protein synthesis
question
Which of the following is the most appropriate pairing of microbe and biosafety level?
answer
methicillin-resistant Staphylococcus aureus (MRSA), BSL-2
question
The dairy creamer used in restaurants is usually treated by
answer
ultra-high-temperature pasteurization
question
Alcohols are used for
answer
both antisepsis and disinfection
question
Which of the following would be used to sterilize a mattress?
answer
ethylene oxide
question
Disinfecting agents naturally produced by microorganisms are
answer
antimicrobials
question
antisepsis
answer
reduction in the number of microorganisms and viruses, particularly potential pathogens, on living tissue
question
aseptic
answer
refers to an environment or procedure free of pathogenic contaminants
question
-cide
-cidal
answer
suffixes indicating destruction of a type of microbe
question
degerming
answer
removal of microbes by mechanical means
question
disinfection
answer
destruction of most microorganisms and viruses on nonliving tissue
question
pasteurization
answer
usse of heat to destroy pathogens and reduce the number of spoilage microorganisms in foods and beverages
question
sanitization
answer
removal of pathogens from objects to meet public heath standards
question
-stasis
-static
answer
suffixes indicating inhibition but not complete destruction of a type of microbe
question
sterilization
answer
destruction of all microorganisms and viruses in or on an object
question
action of boiling of microbial control
answer
denatures proteins and destroys membranes
question
autoclaving action of microbial control
answer
denatures proteins and destroys membranes
question
pasteurization action of microbial control
answer
denatures proteins and destroys membranes
question
ultra high temp sterilization
answer
denatures proteins and destroys membranes
question
hot air action of microbial control
answer
denatures proteins and destroys membranes, oxidizes metabolic compounds
question
incineration action of microbial control
answer
oxidizes everything completely
question
refrigeration action of microbial control
answer
inhibits metabolism
question
freezing action of microbial control
answer
inhibits metabolism
question
desiccation action of microbial control
answer
inhibits metabolism
question
lyophilization action of microbial control
answer
inhibits metabolism
question
filtration action of microbial control
answer
physically separates microbes from air and liquids
question
osmotic pressure action of microbial control
answer
inhibits metabolism
question
ionizing radiation action of microbial control
answer
destroys DNA
question
nonionizing radiation of microbial control
answer
formation of thymine dimers inhibits DNA transcription and replication
question
what is the pore size for membrane filters for the largest viruses and most bacteria?
answer
0.22 micrometers
question
phenol method of microbial control
answer
denatures proteins and disrupts cell membranes
question
phenolics method of microbial control
answer
denatures proteins and disrupts cell membranes
question
alcohols method of microbial control
answer
denatures proteins and disrupts cell membranes
question
halogens method of microbial control
answer
presumably denature proteins
question
oxidizing agents method of microbial control
answer
denature proteins by oxidation
question
surfactants method of microbial control
answer
decrease surface tension of water and disrupt cell membranes
question
heavy metals method of microbial control
answer
denature proteins
question
Aldehydes method of microbial control
answer
denature proteins
question
gaseous agents method of microbial control
answer
denature proteins
question
enzymes method of microbial control
answer
denature proteins
question
antimicrobials method of microbial control
answer
act against cell walls, cell membranes, protein synthesis, and DNA transcription and replication
