Flashcards in Quiz 4 Deck (32):
What is sterilization?
Killing or removal of ALL microorganisms in a substance or on an object.
What is disinfection?
Reducing the number of pathogens in a substance or on an object so that they pose little or no risk of disease.
What is antiseptic?
Inhibits growth or kills microbes. Can be used on living tissue safely.
What is disinfectant?
Destroys microbes on inanimate objects (or in air)--Does NOT kill spores.
What does the suffix -icide mean?
What does sporocide do?
What is bacteriostatic?
An agent that inhibits the growth of bacteria.
What is sanitizer?
A chemical agent used on food handling equipment etc. to reduce microbe numbers ti health standard levels.
Ex: washing with soap or detergent.
What is a germicide?
Substance or agent that destroys harmful microorganisms (antiseptic).
What is the meaning of
Agent that inhibits growth.
What are the methods for physical disruption of microbes?
Heat, UV light, ultrasonic cleaning, microwave, freezing, drying, freeze-drying (lyophilization), and radiation.
What are chemical disruptions of microbes/denature proteins/ruin enzymes?
Heat, pH (acids or strong bases)/hydrolyze, surfactants, and oxidizing agents. They also disrupt membranes.
What are surfactants?
Soluable compounds that reduce surface tension. Penetrates lipids.
What are some examples of disinfectants?
Isopropyl alcohol, phenol, ethyl alcohol, etc.
How does autoclave sterilize?
Steam, pressure, heat and air.
What is the effect of dry heat?
What is the effect of moist heat?
Denatures (disrupts H bonds).
At what time frame does dry heat penetrate?
Slowly, needs hours to sterilize objects. Only method for oils and powders.
What are some specifications on autoclave?
Wet heat penetrates. Short amount of time (15 minutes @ 121 C kills ALL.
What is thimerosal used for?
It is a mercury compound that kills bacteria, fungi, etc. It is used in vaccines as a preservative.
What are some examples of heavy metals used to control microbial growth?
Iodine on cuts, silver nitrate in baby eyes, copper sulfate controls algae and selenium controls fungi.
When mixed with water, alcohol can...
denature proteins and dissolve lipids and membranes. can be used as antiseptic.
disinfect, and does NOT sterilize.
Evaporates in a few seconds.
Does NOT penetrates into skin far enough.
Does NOT kill endospores.
Does NOT cells in skin pores.
What are the two purposes of pasteruization?
Developed to keep wine from going sour. Kills pathogen like mycobacterium and salmonella. Used on milk.
What are the specifications of pasteruization?
63C for not less than 30 minutes.
72C for not less than 16 seconds.
Rise temp to 74C to 140C, then back to 74C in less than 5 seconds.
5C is typical to prevent food from spoiling. Clostridium botulimum found in deep anaerobic in fridges.
-20 degrees keeps microbes from functioning.
Preserves food by low water activity, enzymes inhibited. Endospores survive but make no toxins while drying.
What is the meaning of -static?
Indicating that the agent will prevent the growth of the type of organism in question (e.g., bacteriostatic, fungistatic)
What do phenol and phenolics do?
Disrupt membranes, denature proteins, and inactivate enzymes.