Chapter 11 Flashcards
What are the three methods to destroy or reduce undesirable microbes?
Physical, Chemical, and Mechanical
What are the highest resistance of microbes?
Prions, bacterial endospores
True or False?
Moderate resistance of microbes consist of Pseudomonas sp., Mycobacterium tuberculosis, Staphylococcus aureus, protozoan cysts.
True
Fill in the blank:
LEAST RESISTANCE
1) most bacterial ______ cells
2) _____ spores and ______, yeasts
3) enveloped __________
4) protozoan _________
1) Vegetative
2) fungal and hyphae
3) viruses
4) trophozoites
Define Sterilization
removal or destruction of all viable microbes
Define Germicide:
also called microbicide; any chemical agent that kills pathogenic microorganism, used on inanimate materials or on living tissue, but cannot kill resistant microbial cells
What term means “destruction of vegetative pathogens on inanimate objects”
Disinfection
What term means “chemicals applied to body surfaces to destroy or inhibit vegetative pathogens”
Antisepsis
Define Sanitization:
cleansing technique that removes microorganism and debris from inanimate surfaces
what does suffix “cide” mean
kill the bacteria
what suffix means to inhibit bacteria’s ability to produce
static
What is microbial death?
permanent loss of reproductive capability, even under optimum growth conditions
what are the 4 modes of action of antimicrobial agents
Cell wall, Cell membrane, Nucleic acid synthesis, Alter protein function
Fill in the blank:
Factors that govern the effectiveness of a particular agent
1) _______ time
2) Concentration the _____
3) _______ of organisms
4) __ of the environment
5) Mode of ______
6) Present of ________ or _______ substances
1) Exposure
2) agent
3) Number
4) PH
5) action
6) solvents or interfering
What are the 5 methods of Physical Agents
1) Heat - moist & dry
2) cold temperatures
3) Desiccation
4) Radiation
5) Filtration
What does Moist heat consist of?
Autoclaving, pasteurization, and boiling water
Is pasteurization a method of sterilization?
No, it doesn’t sterilize it kills non-spore forming pathogens and lowers overall microbe count
What’s the difference of between autoclaving and boiling water?
Autoclaving sterilizes and Boiling water disinfects
What’s the difference between Dry and Moist heat
Dry heat uses higher temperatures
What are 2 examples of Dry heat
Dry Oven - used for glassware, metals, powder, oils
Incineration - Bunsen burner for needles/loops
What does refrigeration do?
slows the growth of microbes
What is Desiccation?
removal of water from cells, lead to metabolic inhibition.
-used for foods: raisins, jerky
-Lyophilization: freeze drying/ “snap frozen”
How does radiation work?
occurs as waves or particles bombard molecules in cell. damages DNA=mutations
True or False
Ionizing radiation has a deep penetrating power and can penetrate paper & plastic. Can penetrate cells and breaks DNA. Also consists of Gamma rays (xrays)
True
What kind of radiation is used to cut down microbial loads in medical equipment, loops, and gloves.
Ionizing radiation
Define cold sterilization
sterilize materials that are sensitive to heat or chemicals
Fill in the Blank
Nonionizing Radiation
1) ____ penetrating power
2) must be _____ exposed
3) used to _____ & _____
4) _________ rays
5) UV light creates ______ ______, which interfere with replication
1) little
2) directly
3) sterilize & disinfect
4) Ultraviolet
5) pyrimidine dimers
What is ultraviolet rays used for?
airborne contaminants in hospital & operation rooms, school, waste water
What is the normal UV range wavelength and which length is lethal?
normal: 100nm to 400nm
lethal: 240-280nm
Describe chemical agents
-occur as liquid, gas, or solid
If solid may be dissolved in water (aqueous) and alcohol (tincture)
