18 terms

Chapter 9

The process of using a cleansing technique to mechanically remove and reduce microorganisms and debris to safe levels is
Microbial death occurs when there is
Permanent loss of reproduction.
Which of the following does not affect microbial nucleic acids?
moist heat
Physical agents for controlling microbial growth include all the following except: Pasteurization.
HEPA filters.
Hydrogen peroxide.
Ultraviolet radiation.
Boiling water
Hydrogen peroxide.
Placing organisms at 4oC is
Removal of moisture by dehydration is called
Which of the following items is typically irradiated in order to kill microbes?
- Operating room air
- Human tissues such as heart valves and skin
- Cured meats
- All of the choices are correct.
- Surgical gloves
All of the choices are correct.
Which control method would not be a suitable choice for killing Mycobacterium in a capped culture tube?
ultraviolet (germicidal) light
HEPA filters are used to remove microbes from
Which of the following is not a factor that affects the germicidal activity?
- The material being treated
- All of these are factors.
- The microorganism being treated
-The length of exposure
- The strength of the germicide
All of these are factors
- Is skin degerming agents.
- Disinfect items soaked in alcohol.
- Denature proteins when in a 50-95% alcohol-water solution.
- At 50% or higher concentrations dissolve cell membrane lipids.
- All of the choices are correct.
The chemical agent that produces highly reactive hydroxyl-free radicals and also decomposes to O2 gas is
hydrogen peroxide
All the following act as surfactants except
Quaternary ammonia.
Which of the following is not used as an antiseptic?
Aqueous glutaraldehyde
3% hydrogen peroxide
Aqueous glutaraldehyde
Which of the following acids is not used to destroy or inhibit microbial cells in food?
propionic acid
Lactic acid
Acetic acid
Phosphoric acid
benzoic acid
Phosphoric acid
Antimicrobial agents can target the cell wall by:
Digesting it.
All of the choices are correct.
Blocking its synthesis.
Denaturing proteins
All of the choices are correct.
Bacteriostatic agents kill bacterial cells
Prions require more extensive methods of sterilization than are needed for bacterial endospores