Microbio Ch9
Why do younger, active cells die more quickly when exposed to microbicidal agents? 1. They are more metabolically active 2. they have greater oxygen requirement 3. they are weaker and less mature. 4. they are more numerous in number.
They are more metabolically active
True or false: cold treatment and dessication cannot be reliable used for sterilization or disinfection
True
True/ false: the primary targets of microbial control are microorganisms that cause infection or spoilage
True
__ is the process by which material are subjected to intermittent sterilization.
Tyndallization
What is sterilization? 1. a process that completely removes or destroys all vegetative micoorganisms, including viruses, from an object or habitat 2. a process that completely removes or destroys all viable microorganisms, including viruses, from an object or habitat 3. a process that completely removes or destroys all viable microorganisms, except viruses, from an object or habitat
a process that completely removes or destroys all viable microorganisms, including viruses, from an object or habitat
___ are limited in their application because they are corrosive and hazardous. 1. chlorines 2. phenol derivatives 3. aldehydes 4. acid and alkalis
acid and alkalis
UV radiation is effective at disinfecting which types of materials? 1. air 2. liquids 3. solid surfaces 4. entire solid objects
air liquids solid surfaces
degermation and __ can be accomplished with the same procedure
antisepsis
Antimicrobial solutions with water as the solvent are called___ solutions, whereas antimicrobial solutions with alcohol or water-alcohol mixtures as the solvent are called__.
aqueous; tinctures
What microbial agent is the most resistant to physical and chemical control methods? 1. fungai spores 2. bacterial endospores 3. protozoan cysts 4. mycobacterium cells
bacterial endospores
Which type of agent will kill bacteria? 1. bactericidal 2. bacteristatic
bactericidal
A__ agent will inhibit the growth of bacteria, whereas a __agent will kill bacteria
bacteriostatic; bactericidal
Which of the following are examples of disinfection? 1. boiling eating utensils 2. cleansing a wound with a bleach solution 3. a 5% solution of bleach to clean a lab table 4. Immersing thermometers in an iodine solution
boiling eating utensils a 5% solution of bleach to clean a lab table Immersing thermometers in an iodine solution
Which of the following are some of the desirable qualities in a germicide? 1. broad-spectrum action 2. penetrating ability 3. rapid action 4. selective toxicity 5. narrow-spectrum action 6. inactivated by organic matter 7. solubility in a solvent
broad-spectrum action penetrating ability rapid action selective toxicity solubility in a solvent
antiseptic are __agents applied to the skin to inhibit vegetative bacterial cells. 1. chemical and physical 2. chemical 3. physical
chemical
gaseous and liquid__ compounds are mostly used for large-scale water disinfection.
chlorine
__ is the mechanical removal of most microbes from an animate or inanimate surface.
decontamination
Surgical handscrubbing is an example of: 1. sterilization 2. degermation 3. disinfection
degermation
__ and antisepsis can be accomplished with the same procedure. 1. sterilization 2. degermation 3. pasteurization
degermation
__ is the physical removal of surface oils, debris, and soil from skin to reduce the microbial load.
degermation
alcohols are commonly used for: 1.degermation of skin 2. household cleaning 3. disinfection of drinking water 4. disinfection of food preparation equipment 5. antiseptic preparation for skin
degermation of skin antiseptic preparation for skin
The disruption of proteins from their native state is known as __.
denaturation
Chlorine compounds typically kill microbes by: 1. inhibiting RNA synthesis 2. denaturing metabolic enzymes 3. disrupting the cell membrane 4. causing mutations in DNA 5. inhibiting protein synthesis
denaturing metabolic enzymes
high concentrations of alcohols usually affect microbes by: 1. denaturing proteins 2. inhibiting protein synthesis 3. inhibiting RNA synthesis 4. causing mutation in DNA 5. disrupting the cell wall
denaturing proteins
iodine compounds typically kill microbes by: 1.inhibiting protein synthesis 2. denaturing proteins 3.causing mutation in DNA 4. disrupting the cell membrance 5. inhibiting RNA synthesis
denaturing proteins
___ is the dehydration of microorganism in order to inhibit or preserve them.
desiccation
If an agent disrupts the cell wall, the cell is likely to experience: 1. reduced metabolism 2. digestion or breakdown of the cell wall 3. loss of selective permeability 4. an inability to synthesize proteins
digestion or breakdown of the cell wall
Chlorhexidine typically kills microbes by: 1. Causing mutations in DNA 2. Inhibiting RNA synthesis 3. Inhibiting protein synthesis 4. disrupting the cell wall 5.disrupting the cell membrane 6. denaturing protein
disrupting the cell membrane denaturing protein
An object can be: 1. either sterile or not sterile 2. sterile, mostly sterile, or not sterile 3. several degrees of sterility
either sterile or not sterile
high-level germicides can kill__, whereas intermediate-level germicides can kill fungal spores and resistant pathogen but not endospores.
endospores
alcohols are effective against: 1. enveloped viruses 2. bacterial endospores 3. fungi 4. most bacteria
enveloped viruses fungi most bacteria
Chlorine compounds usually kill microbes by denaturing metabolic __.
enzyme
Which two alcohols are effective in microbial control? 1. methyl 2.ethyl 3. butyl 4. isopropyl
ethyl isopropyl
___ oxide is valuable for sterilization of heat-sensitive objects such as plastics, surgical and diagnostic appliances, and spices, but other related gases are available that are less toxic.
ethylene
__oxide is valuable for sterilization of heat-sensitive objects such as plastics, surgical and diagnostic appliances, and spices, but other related gases are available that are less toxic. 1. fomaldehyde 2.propylene 3. ethylene 4. Chlorine
ethylene
Which of following compounds are commonly used as gaseous sterilants or disinfectants? 1. ethylene oxide 2. chlorine dioxide 3. carbonic acid 4. carbon monoxide
ethylene oxide chlorine dioxide
The effect of a germicide is affected by the time of____.
exposure
A common dry heat sterilization method used in the microbiology laboratory is: 1. autoclaving used culture tubes 2. tyndallization of cultures 3. flaming the inoculating loop 4. heating agar in boiling water
flaming the inoculating loop
The __ method od pasteurization exposes liquids to higher temperature for a very short time, whereas the __ method uses lower temperatures for a longer period.
flash; batch
__ is an aqueous solution of formaldehyde gas that is used as a potent chemical fixative and microbicide.
formalin
__ are chemical agents that kill non-endospore forming pathogens. 1.germicides 2. germistatins 3. insecticide
germicides
Which of the following is the most common physical agent used to control microbes? 1. filtration 2. cold 3. heat 4. dessication 5. radiation 6. germicide
heat
In most cases, an agent with a __ concentration will be more germicidal. 1.high 2. low
high
disinfectants can be toxic or harmful to__ and __ tissues
human; animal
__ __ typically kills microbes by producing toxic radicals.
hydrogen peroxide
The use of sugar or salt to preserve food create a __ environment for the bacteria in the foods.
hypertonic
Heavy metal typically kills microbes by: 1. producing toxic radicals 2. causing mutation in DNA 3. disrupting the cell wall 4. inactivating proteins 5. inhibiting RNA synthesis 6. disrupting the cell membrane
inactivating proteins
sterilization methods are usually reserved for: 1. inanimate objects 2.living tissue
inanimate objects
__is the destruction of microbes by subjecting them to extremes of dry heat, reducing them to ashes and gas.
incineration
Which are example of using dry heat to sterilize materials? 1.tyndallization 2. autoclaving 3. incineration 4. pasteurization 5. hot air oven
incineration hot air oven
A(n)___ is a combination of iodine and an organic carrier (such as alcohol) that serves as a moderate-level disinfectant and antiseptic.
iodophor
The two primary iodine preparation are free iodine and ___.
iodophors
__ are complexes of iodine and alcohol.
iodophors
Both__and __ forms of radiation can be used to control the growth of microorganisms.
ionizing; nonionizing
Which of the following should be considered when initially choosing a method of microbial control? 1. is it cost and labor-efficient? 2. what is the temperature and pH of environment? 3. Is it safe? 4. Are the cells in the culture old or new? 5. Is sterilization needed? 6. Is the item reusable or disposable? 7. will it penetrate effectively? 8. can it withstand physical or chemical treatments?
is it cost and labor-efficient? Is it safe? Is sterilization needed? Is the item reusable or disposable? will it penetrate effectively? can it withstand physical or chemical treatments?
bactericides__ bacteria. 1. kill 2. enhance the growth of 3. inhibit the growth of
kill
heavy metals: 1. prevent microbial growth 2. kill microbes
kill microbes
Gaseous and liquid chlorine compounds are mostly used for: 1.food equipment sanitation 2. household cleaning 3. wound treatment and skin cleansing 4. large-scale water disinfection
large-scale water disinfection
The disadvantage of UV radiation include the inability to penetrate___ or solids.
liquid
What is the major disadvantage of the dry oven in sterilization? 1.unreliable results 2. safety concerns 3. long time requirement 4. ineffective against viruses
long time requirement
quaternary ammonium compounds are considered to be__-level disinfectants.
low
Quats are rated as ___ disinfectant in the clinical setting. 1. intermediate-level 2. high-level 3.low-level
low-level
Which of the following heavy metals are still used in germicidal preparations? 1. mercury 2. silver 3. arsenic 4. copper 5. gold 6. zinc
mercury silver
agents that are highly selective in their targets are usually effective against a __ range of microbes. 1. wide 2. narrow
narrow
The __ __ quantitatively compares the effectiveness of a chemical to that of phenol.
phenol coefficient
Temperature and radiation are two __ methods used to control microbes. 1. physical 2. chemical 3. mechanical
physical
What type of macromolecules are affected by heavy metals? 1. peptidoglycan 2. proteins 3. nucleic acids 4. phospholipids
protein
Which of the following are goals of pasteurization? 1. destruction of endospores 2. reduction of microbial load 3. sterilization of liquid 4. destruction of pathogens 5. retention of liquid qualities
reduction of microbial load destruction of pathogens retention of liquid qualities
Which of the following factors can influence the action of antimicrobial agents? 1. motility of the organisms 2. relative resistance of population 3. microbial load 4. oxygen concentration of environment 5. temperature of environment 6. presence of interfering matter 7. concentration and action of agent
relative resistance of population microbial load temperature of environment presence of interfering matter concentration and action of agent
The synthesis of proteins involves organelles known as __ in a process called translation
ribosomes
Washing laundry, doing dishes, and wiping down counters with soap are all examples of: 1. sterilization 2. disinfection 3. sanitization 4. antisepsis
sanitization
soap and quats are commonly used for: 1. disinfection of drinking water 2. sanitization of home 3. disinfection of medical equipment 4. sanitization of food preparation equipment 5. sterilization of diagnostic instruments 6. skin cleansing 7. disinfection of facilities
sanitization of home, sanitization of food preparation equipment, skin cleansing, disinfection of facilities
__ and mercury are heavy metals that are still used in germicidal preparations.
silver
antiseptics are used to destroy vegetative bacteria on: 1. inanimate surfaces 2. skin 3. internal surfaces 4. animate and inanimate object
skin
The main effect of cold treatment is to: 1. kill a majority of microbes 2. slow the activity of microbes
slow the activity of microbes
What type of agent specifically destroys bacterial endospores? 1. sporicide 2. virucide 3. Fungicide 4. bactericide
sporicide
An autoclave is a sterilization chamber that allows the use of __ to sterilize materials. 1. high-level germicides 2. steam under pressure 3. boiling water 4. intermittent steam
steam under pressure
Chemical agents that can destroy all form of life, including spores are called__.
sterilants
An object is __ if it is free of all viable microorganisms including viruses.
sterile
A process that completely removes or destroys all viable microorganisms, including viruses, from an object or habitat is referred to as ___.
sterilization
The goal of __ is to remove or destroy all viable microorganisms including viruses.
sterilization
Glassware are liquids may be successfully__ in the autoclave. 1. sanitized 2. sterilized 3. disinfected
sterilized
What is the thermal death time? 1. the time it takes to reduce a microbial population to safe level 2. the lowest temperature at which all microbes are killed within ten minute 3. the shortest length of time require to kill all test microbes at a specific temperature
the shortest length of time require to kill all test microbes at a specific temperature
What is incineration? 1. the use of dry heat to destroy all microbes 2. the use of steam to destroy all microbes 3. the use of moist heat to destroy most microbes
the use of dry heat to destroy all microbes
Nucleic acid play which role(s) in microbial function? 1. they protect the cell from foreign chemical 2. they drive the production of proteins 3. they must be replicated prior to binary fission 4. They speed up the rate of metabolism
they drive the production of proteins they must be replicated prior to binary fission
Nucleic acids play which role(s) in microbial function? 1. they protect the cell from foreign chemicals 2. they speed up the rate of metabolism 3. they drive the production of proteins 4. they must be replicated prior to binary fission
they drive the production of proteins they must be replicated prior to binary fission
Also called intermittent sterilization, __ is the use of repeated steaming and incubation cycles for sterilization.
tyndallization
Which are examples of using moist heat to sterilize or disinfect materials? 1. tyndallization 2. hot air oven 3. incineration 4. boiling 5. autoclaving 6. pasteurization
tyndallization boiling autoclaving pasteurization
Which of the following is/are types of nonionizing radiation? 1. cathode rays 2.gamma rays 3. ultraviolet rays 4. x-ray
ultraviolet rays
What is a concern when attempting to control a microbial population? 1. uniformity of the population 2. variable resistance 3. microbial antagonism
variable resistance
Chlorohexidine can kill/ inactivate most: 1. viruses 2. bacteria 3. endospores
viruses bacteria
Aldehydes are organic substances that contains a__ functional group on a terminal carbon. 1. -CHO 2. -OH 3. -HOH 4.-CH
-CHO
Which method of pasteurization uses a lower temperature for a longer period of time? 1. Batch method 2. Flash method
Batch method
True or false: acids and alkalis are commonly used for drinking water disinfection.
False
__ is one of the few chemical that is officially accepted as a sterilant and high-level disinfectant.
Glutaraldehyde
___and ethylene oxide are two of the few chemical that are officially accepted as sterilant and high-level disinfectants.
Glutaraldehyde
__ is a method for preserving microorganisms (and other substances) by freezing and then drying them directly from the frozen state.
Lyophilization
heavy metal are reliably: 1. microbistatic 2. Sporicidal 3. Microbicidal
Microbicidal
Any process or agent that inhibits microbial growth is referred to as__.
Microbistatic
___ is a technique in which heat is applied to liquid to kill potential agents of infection and spoilage.
Pasteurization