MICRO chp 7 Flashcards
What is sterilization?
Destruction and/or removal of all microbes and their spores/cysts.
Prions may still survive.
Define vegetative microbe.
A microbe in a functional state, capable of growth and reproduction.
What is a spore/cyst?
A microbe in a hibernating state, capable of surviving extreme conditions.
What does it mean for a spore to germinate?
To turn back into vegetative microbes when certain environmental conditions occur.
What is sepsis?
Microbial contamination.
What is commercial sterilization?
Conditions sufficient to destroy endospores of Clostridium botulinum.
How is commercial sterilization different from regular sterilization?
More limited than regular sterilization.
What is sanitization?
Removal or destruction of vegetative microbes to low enough levels for public safety.
What is disinfection?
Destruction of all vegetative microbes.
What is antisepsis?
Disinfection of living tissue.
Define degermation.
Mechanical removal of vegetative microbes.
What is a germicide?
A substance or treatment capable of destroying microbes.
What are germistatic compounds?
Substances capable of inhibiting microbial growth (but not killing them).
What is one of the most common methods of destroying microbes?
Heat.
How do high temperatures affect microbial cells?
Denature proteins in microbial cells, leading to cell death.
Name three methods of heat sterilization.
- Moist heat sterilization
- Dry heat sterilization
- Pasteurization
What effect do low temperatures have on microbes?
Often have a germistatic effect.
What is pasteurization?
Mild heating methods to kill pathogenic or food-spoilage bacteria.
Who first described pasteurization?
Louis Pasteur.
What is the primary use of filtration?
To remove microbes from liquids or gases.
What determines what can pass through a filter?
The size of the pores.
What is non-ionizing radiation?
UV rays.
What is ionizing radiation?
X-rays, gamma rays.
What is desiccation?
The removal of water from organic matter.
