Exam 4- Control of Microbial Growth- Ch 7
Can be used for both skin disinfection and wound treatment A. Triclosan B. hexachlorophene C. Chlorhexidine D. Betadine
Betadine
Most commonly used in iodophor A. Triclosan B. hexachlorophene C. Chlorhexidine D. Betadine
Betadine
Chlorhexidine is a member of this group A. Biphenols B. Halogens C. Aldehydes D. Biguanide
Biguanide
Kills microorganisms A. Biocides B. fungicides C. virucide D. bacteriostasis E. spesis
Biocides
True/False Disinfectants work better under colder temps
False They work better under warm temps
chemical type used for controling microbes
Heavy metals: denature protein and are effective in small amounts. ( silver, mercury, copper,zinc)
To which category do iodine and chlorine belong? A) biguanide B) halogen
halogen
While waiting for your meal at a restaurant, you read the information on the creamer containers at your table and notice that they do not need to be refrigerated. You are surprised, because dairy products typically must be kept cold to prevent spoilage. How were these products treated to eliminate microbial growth and prevent spoilage? A. UHT treatment B. chemical preservatives C. gamma irradiation D. pasteurization
UHT treatment Ultra-high-temperature (UHT) is a treatment that essentially sterilizes the product
Which of the following shows the moist heat methods in order of the temperature used (highest to lowest)? A. Ultrahigh>Boiling>Autoclave>Batch Pasteurization B. Ultrahigh>Autoclave>Boiling>Batch Pasteurization C. Autoclave>Ultrahigh>Batch Pasteurization>Boiling D. Ultrahigh> Boiling>Batch Pasteurization >Autoclave
Ultrahigh>Autoclave>Boiling>Batch Pasteurization
autoclaving
Use of steam under pressure- 15 psi @ 121C for 15 min
True/ False Soap has little value as an antiseptic. It is only used as a mechanical means to remove microbes
True
True/ False Steam under pressure fails to sterilize when the air is not completely exhausted
True
True/ False The more microbes there are to begin with, the longer it takes to eliminate the entire population
True
True/False Aspetic technique is important in surgery to minimize contamination
True
True/False Ethylene oxide gas is used to sterilize medical equipment that might be damaged by exposure to the heat of autoclaving
True
True/False HEPA filters are used to remove microorganisms from the air
True
True/False Ionizing radiation can be used to sterilize some foods such as spices, meat, and fruits and vegetables.
True
True/False Some species of Pseudomonas not only survive in QUATS but actively grow in them
True
True/False The presence of organic matter, such as blood or saliva, may impair the action of antimicrobial chemicals
True
True/False Times required for sterilization in an autoclave are shorter than those required in a dry oven because moist heat penetrates biological specimens more effectively than does dry heat.
True
True/False When water is made available, after desiccation, micrboes can resume their growth and division
True
What are more resistant to disinfectants and antiseptics A. gram-negative bacteria B. gram-positive bacteria
gram-negative bacteria
Formaldehyde is a member of this group A. Biphenols B. Halogens C. Aldehydes D. Biguanide
Aldehydes
Chlorine is a member of this group A. Biphenols B. Halogens C. Aldehydes D. Biguanide
Halogens
autoclave
steam under pressure, provides reliable sterilization,
virus
not especially resistant to biocide
-cidal
killing m/o
control of m/o: heat
oldest and most widely used way of controling m/o
-static
stop m/o growth
True/False Most viruses are highly resistant to disinfectants and antiseptics
False
antisepsis
chemical on living skin for disinfection
way to kill microbes
damage to nucleic acids
sanitization
lowering m/o to safe public health standards
biocides
not uniformly effective against all microbes
physical type used for controling microbes
radiation: Uv rays, gamma rays
pasteurization
reduces spoilage organisms and pathogens
Factors in chemical Method of controling m/o
-number and types of microbes -concentration of the agent -nature of material: presence of organic material, pH, temp.
Factors in physical method of controling m/o
- number and types of microbes -nature of the material to be treated -environment: presence of organic material, moisture, pH, temp -cost
ultra high temperature UHT
140 degrees for 4 sec, milk does not need to be refridgerated
Food with a pH of ___ or ____, are most susceptible to spoilage by molds A. 7.0, higher B. 5.5, lower C. 9.6, higher D. 7.0, 8.3
5.5, lower
Alcohol is most effective when used as a ________ solution. A. 95% B. 100% C. 60% D. 70% E. 25%
70%
Which concentration of ethanol is the most effective bactericide? A. 100% B. 70% C. 50% D. 40% E. 30%
70%
high temperature short times HTST
72 degrees for 15 sec, most milk pasteurization
A nurse is degerming a patient's arm before giving a vaccination. Which of these concentrations of alcohol is most effective? A. 100% B. 75% C. 50% D. 25%
75% Alcohols work by denaturing proteins, and this process requires water. Generally, the most effective alcohol concentration is 70%.
The decimal reduction time is the time required to kill __________ percent of a bacterial population
90%
True/ False One advantage of alcohol is that they act then evaporate rapidly and leave no residue
True
The two microbes most resistant to biocides (pick two) A. prions B. endospores C. viruses with lipid envelopes D. gram-positive bacteria E. gram-negative bacteria
A. prions B. endospores
Their sanitizing ability is related to the negatively charged portion if the molecule, which reacts with the plasma membrane A. QUATS B. Acid-Anionic Sanitizers C. Aldehydes D. Halogens
Acid-Anionic Sanitizers
These sanitizers act on thermoduric bacxteria, nontoxic, noncorrosive and fast-acting A. QUATS B. Acid-Anionic Sanitizers C. Aldehydes D. Halogens
Acid-Anionic Sanitizers
Effectively kill bacteria and fungi but not endospores and nonenveloped viruses A. Alcohol B. Metals C. Chlorhexidine D. Iodine
Alcohol
Which disinfectant exerts their action by denaturing proteins and dissolving lipids A. Alcohol B. Metals C. Chlorhexidine D. Iodine
Alcohol
When this two components are combined they make Avagard, which is a biguanide A. Iodine and chlorhexidine B. Alcohol and chlorhexidine C. Triclosan and Alcohol D. phenol and chlorine
Alcohol and chlorhexidine
chemical type used for controling microbes
Alcohols: works by protein denaturation and disruption of lipids.
Glutaraldehyde is a member of this group A. Biphenols B. Halogens C. Aldehydes D. Biguanide
Aldehydes
The MOST effective antimicrobial A. Biphenols B. Halogens C. Aldehydes D. Biguanide
Aldehydes
chemical type used for controling microbes
Aldehydes: work by inactivating proteins and nucleic acids(formaldehyde, gluteraldehyde,cidex)
True/False Iodine is one of the least effective antimicrobial chemicals, effective only against certain very sensitive strains of bacteria.
False
By definition, a tincture contains alcohol. Why would a tincture of an antiseptic be more effective than an aqueous solution? A. Alcohol contributes to the effectiveness of an antiseptic because it denatures proteins. B. Alcohol contributes to the effectiveness of an antiseptic because it dissolves lipids. C. Answers A and B are both correct. D. Neither answer A nor B is correct
Answers A and B are both correct
Treatment is directed at living tissue A. sterilization B. Antisepsis C. Disinfection D. Degerming E. Sanitization
Antisepsis
Best way to sterilize A. boiling B. Autoclaving C. pasteurization D. Dry heat sterilization
Autoclaving
Temp must be above 100 degree celsius in order to kill all forms of life. A. boiling B. Autoclaving C. pasteurization D. Dry heat sterilization
Autoclaving
Used in hospital environments to sterilize equipment A. boiling B. Autoclaving C. pasteurization D. Dry heat sterilization
Autoclaving
Effective against gram-positive and gram-negative bacteria except pseudomonads A. Biphenols B. Halogens C. Aldehydes D. Biguanide
Biguanide
This disinfectant damages the plasma membrane of vegetative cells A. Biphenols B. Halogens C. Aldehydes D. Biguanide
Biguanide
Hexachlorophene is a member of this group A. Biphenols B. Halogens C. Aldehydes D. Biguanide
Biphenols
Triclosan is a member of this group A. Biphenols B. Halogens C. Aldehydes D. Biguanide
Biphenols
Used to destroy green algae that grows in reservoirs, stock ponds, swimming pools and fish tanks A. silver-sulfadiazine B. Mercuric chloride C. Copper sulfate
Copper sulfate
The MOST vulnerable forms of microbes to biocides are: (pick two) A. prions B. endospores C. viruses with lipid envelopes D. gram-positive bacteria E. gram-negative bacteria
C. viruses with lipid envelopes D. gram-positive bacteria
supercritical fluid
CO2 is compressed into supercritical state (properties of gas and liquid), inactivates most vegetative organisms that cause spoilage and foodborne pathogens, medical implants and bone, tendon and ligament from donor patients
An effective fungistat used in bread, prevents the growth of surface molds and bacillus bacterium A. Sodium nitrate B. Calcium propionate C. Mercuric chloride D. Copper sulfate
Calcium propionate
These organic acids interfer with mold's metabolism or the integrity of the plasma membrane A. Sodium nitrate B. Calcium propionate C. Mercuric chloride D. Copper sulfate
Calcium propionate
Used in hospital surgical scrubs A. Triclosan B. Chlorine C. Hexachlorophene (pHisoHex) D. Chlorhexidine
Chlorhexidine
Germicidal action, is based on when this disinfectant is added to water to create hypochlorous acid A. formaldehyde B. hexachlorophene C. Chlorhexidine D. Chlorine
Chlorine
Used to disinfect drinking water, swimming pools and sewage A. formaldehyde B. hexachlorophene C. Chlorhexidine D. Chlorine
Chlorine
Widely used disinfectant either as a gas or liquid A. formaldehyde B. hexachlorophene C. Chlorhexidine D. Chlorine
Chlorine
Which one is not paired correctly A. Triclosan - Bisphenol B. Chlorhexidine - Biguanide C. Formaldehyde - Aldehydes D. Chlorine - Alcohol
Chlorine - Alcohol
The time in minutes, in which 90% of the population of bacteria at a given temp will be killed A. Decimal reduction time B. Thermal death time C. Thermal death point
Decimal reduction time
The mechanical removal of most microbes in an area A. sterilization B. Antisepsis C. Disinfection D. Degerming E. Sanitization
Degerming
When skin is cleaned with alcohol prior to an injection A. sterilization B. Antisepsis C. Disinfection D. Degerming E. Sanitization
Degerming
The destruction of vegetative pathogens that do not form endospores A. sterilization B. Antisepsis C. Disinfection D. Degerming E. Sanitization
Disinfection
Kills by oxidation effects A. boiling B. Autoclaving C. pasteurization D. Dry heat sterilization
Dry heat sterilization
Some microbes are very resistant to antimicrobial chemicals. Which of the following would be the easiest to kill? A. Mycobacterium tuberculosis B. E. coli. C. cysts of protozoa D. Pseudomonas aeruginosa E. Clostridium endospores
E. coli
What are vital to cellular activity A. cell wall B. plasma membrane C. Enzymes D. Nucleic acid
Enzymes
chemical type used for controling microbes
Ethylene Oxide(ETO): can sterlize material by denaturing proteins such as surgical plastics,porous material such as pillows and mattresses. Must be used in an autoclave type chamber.
True/ False Microorganisms placed in high concentrations of salts and sugars undergo lysis.
False
True/ False Prions are not resistant to disinfectants and autoclaving
False
True/ False The pH of the medium has no effect on the activity of the disinfectant being applied.
False
True/False All bacteria die at once when they are exposed to heat or chemical treatment
False
True/False Hydrogen peroxide is a good antiseptic for open wounds
False
True/False Soap is ineffective in killing bacteria. Therefore, hand washing is a rather ineffective measure in preventing disease transmission.
False
True/False The presence of organic matter does not inhibit the action of chemical antimicrobials
False
True/False UV radiation and x-ray radiation are similar in that they damage DNA and have a high penetrating power
False
True/False When milk is pasteurized it is made sterile
False
True/ False Biocides work on microbes in biofilms
False Biocides do NOT reach microbes in biofilms because their activity is due to temp-dependent chemical reactions
True/ False Most chemical agents achieve sterility
False Few chemical agents achieve sterility
Why would filter sterilization be used rather than heat, such as autoclaving? A. Filter sterilization is less expensive than autoclaving. B. Filter sterilization is used when the contents of the liquid could be harmed by heat. C. Filter sterilization is more effective than autoclaving
Filter sterilization is used when the contents of the liquid could be harmed by heat
This is used to sterilize heat-sensitive materials, such as culture media, enzymes, vaccines and antibiotic solutions A. Low Temps B. Moist Heat C. Filtration D. High Pressure E. Osmotic Pressure
Filtration
Which filter is used to remove microorganisms from the air A. Membrane filter B. HEPA filter
HEPA filter
filtration
HEPA filters remove microbes > 0.3um; membrane filters remove microbes > 0.22um; used for heat sensitive materials, enzymes, vaccines, antibiotic solutions
Iodine is a member of this group A. Biphenols B. Halogens C. Aldehydes D. Biguanide
Halogens
chemical type used for controling microbes
Halogens: Iodine, chlorine
__________ bacteria may survive pasteurization
Heat resistant
True/ False Pseudomonas has been found growing in quaternary ammonium compounds (quats).
True
Gram-positive staphylococci and streptococci are susceptible A. Triclosan B. Chlorine C. Hexachlorophene (pHisoHex) D. Chlorhexidine
Hexachlorophene (pHisoHex)
This bisphenol is used for hospital microbial control during procedures A. Triclosan B. Chlorine C. Hexachlorophene (pHisoHex) D. Chlorhexidine
Hexachlorophene (pHisoHex)
If the pressure is _____ enough, it alters the molecular structures of proteins and carbohydrates. A. Low B. High
High
Advantage of this method is that it preserves the flavors, colors, and nutrient values of products A. Low Temps B. Moist Heat C. Filtration D. High Pressure E. Osmotic Pressure
High Pressure
Pasteurizing at 72C for 15minutes to kill pathogens as well lowers total bacterial counts A. Hot-air sterilization B. High-temp short-time (HTST) pasteurization C. flaming D. ultra-high temp treatment (UHT)
High-temp short-time (HTST) pasteurization
Sterilization by the use of an oven at 170C for 2hours A. Hot-air sterilization B. High-temp short-time (HTST) pasteurization C. flaming D. ultra-high temp treatment (UHT)
Hot-air sterilization
This disinfectant quickly breaks down into water and gaseous oxygen by the action of the enzyme catalase. A. Hydrogen Peroxide B. Plasma C. Peracetic acid D. Alcohol
Hydrogen Peroxide
60 minutes
In the figure, what is the thermal death time? A. 150°C B. 120 minutes C. 100°C D. 60 minutes E. The answer cannot be determined.
Used in resin filters for water treatment A. Triclosan B. hexachlorophene C. Chlorhexidine D. Iodine
Iodine
What can be combined with certain amino acids to inactivate enzymes and other cellular proteins A. Alcohol B. Metals C. Chlorhexidine D. Iodine
Iodine
What is effective against all kinds of bacteria, many endospores, various fungi, and some viruses A. Triclosan B. hexachlorophene C. Chlorhexidine D. Iodine
Iodine
Forms highly reactive hydroxyl radicals that damage cellular components A. Ionizing radiation B. Nonionizing radiation
Ionizing radiation
Uses gamma rays , X-rays, and high-energy electron beams A. Ionizing radiation B. Nonionizing radiation
Ionizing radiation
Nitrate inhibits _____ containing enzymes A. Copper B. Iron C. Mercury D. Silver
Iron
Which of the following is a limitation of the autoclave? A. It requires an excessively long time to achieve sterilization. B. It cannot be used with glassware. C. It cannot inactivate viruses. D. It cannot be used with heat-labile materials. E. It cannot kill endospores
It cannot be used with heat-labile materials
Plasma sterilization requires A. Low Temps B. Moist Heat C. Filtration D. High Pressure
Low Temps
What type of filter is when a sample needs to be sterilized. A. Membrane filter B. HEPA filter
Membrane filter
inorganic compound that is used as a disinfectant A. silver-sulfadiazine B. Mercuric chloride C. Copper sulfate
Mercuric chloride
bacterial endospores
are very resistant to biocide
What affects the choice of chemical and physical control methods A. Time of exposure B. Environment C. Number of microbes D. Microbial characteristics
Microbial characteristics
What resists osmotic pressure the most A. vegetative bacteria B. Molds and yeasts C. pathogenic bacteria
Molds and yeasts
This type of radiation is used to control microbes in the air, such as in hospital rooms, nurseries, and cafeterias A. Ionizing radiation B. Nonionizing radiation
Nonionizing radiation
Uses UV light A. Ionizing radiation B. Nonionizing radiation
Nonionizing radiation
Cells can no longer replicate, nor can it carry out normal metabolic functions if there is damage to what A. cell wall B. plasma membrane C. Enzymes D. Nucleic acid
Nucleic acid
chemical type used for controling microbes
Organic acids: added to foods to retard spoilage by altering the plasma membrane of m/o (sorbic acid, benzoic acid, calcium propionate,sodium nitrite)
This processes uses high concentrations of salts and sugars to cause water to leave cells A. Low Temps B. Moist Heat C. Filtration D. High Pressure E. Osmotic Pressure
Osmotic Pressure
This process resembles preservation by desiccation, denying it the moisture to grow A. Radiation B. Osmotic pressure C. Filtration D. High Pressure
Osmotic pressure
chemical type used for controling microbes
Oxidizing Agents: hydrogen peroxide,benzoyl peroxide, ozone with chlorine, peracetic acid.
_______________ is a process used to destroy pathogens in food and drinks. It must be done at a lower temperature than other methods so that _______________. A. autoclaving; beneficial microorganisms are not killed B. Pasteurization; beneficial microorganisms are not killed C. autoclaving; the taste of the food or drink will not be altered D. Pasteurization; the taste of the food or drink will not be altered
Pasteurization; the taste of the food or drink will not be altered
One of the most effective liquid chemical sporicides available and can be used as a sterilant A. Hydrogen Peroxide B. Plasma C. Peracetic acid D. Alcohol
Peracetic acid
A group of oxidizing agents that include hydrogen peroxide and peracetic acid A. Peroxygens B. Halogens C. Aldehydes D. Biguanide
Peroxygens
These disinfectant damage to plasma membrane, resulting in leakage of cellular contents A. Biphenols B. Halogens C. Aldehydes D. Phenolics
Phenolics
These disinfectants remain active in the presence of organic material such as pus, saliva, and feces A. Biphenols B. Halogens C. Aldehydes D. Phenolics
Phenolics
This dicinfectant was first used by Joseph Lister to control surgical infections in the OR A. Biphenols B. Halogens C. Aldehydes D. Phenolics
Phenolics
Used in throat lozenges A. Biphenols B. Halogens C. Aldehydes D. Phenolics
Phenolics
What is the main ingredient in the product lysol A. Biphenols B. Halogens C. Aldehydes D. Phenolics
Phenolics
chemical type used for controling microbes
Phenolics: (derivatives of phenol) -work by disrupting the plasma membranes -they do not sterilze -less irritating, remain active in the presence of organic compounds
A state of matter in which a gas is excited to make a mixture of nuclei with assorted electrical charges and free electrons A. Hydrogen Peroxide B. Plasma C. Peracetic acid D. Alcohol
Plasma
This has free radicals that quickly destroy endopore-forming microbes A. Hydrogen Peroxide B. Plasma C. Peracetic acid D. Alcohol
Plasma
You are preparing a medium for growing fastidious bacteria and must add several heat-labile solutions of growth factors. Which of the following is an appropriate strategy for preparing and sterilizing this medium? A. Prepare and autoclave the medium before adding the growth factors. After the medium has cooled, filter sterilize and aseptically add the growth factors. B. Use UV radiation to sterilize this medium. C. Use dry heat to sterilize the medium. D. Prepare the medium, add the growth factors, and autoclave. E. Pasteurize the medium.
Prepare and autoclave the medium before adding the growth factors. After the medium has cooled, filter sterilize and aseptically add the growth factors.
MOst widely used surface agents, they are related to the positively charged portion of the molecule A. QUATS B. Acid-Anionic Sanitizers C. Aldehydes D. Halogens
QUATS
They are strongly bactericidal, fungicidal, amebicidal, and virucidal against enveloped viruses A. QUATS B. Acid-Anionic Sanitizers C. Aldehydes D. Halogens
QUATS
__________ ammonium compounds are less effective against gram-negative bacteria and more effective against gram-positive bacteria.
Quaternary
chemical type used for controling microbes
Quats: (Quaternary Ammonium compounds) positively charged that affect the plasma membrane. They work better on gram+ and are not effective against endospores and mycobacteria. ex: Benzalkonium chloirde, Zephiran,cetylpyridium chloride (cepacol)
HIgh energy electron beams are used for the sterilization of pharmaceuticals and disposable dental and medical supplies A. Radiation B. Osmotic pressure C. Filtration D. High Pressure
Radiation
Ionization of water, which forms highly reactive hydroxyl radicals that damage cellular components A. Radiation B. Osmotic pressure C. Filtration D. High Pressure
Radiation
Treatment intended to lower microbial counts on eatting and drinking utensils to safe public health levels A. sterilization B. Antisepsis C. Disinfection D. Degerming E. Sanitization
Sanitization
When a restaurant washes its dishes in a high-temp dishwasher A. sterilization B. Antisepsis C. Disinfection D. Degerming E. Sanitization
Sanitization
Added to meat products A. Sodium nitrate B. Calcium propionate C. Mercuric chloride D. Copper sulfate
Sodium nitrate
Prevent germation and growth of any botulism endospores A. Sodium nitrate B. Calcium propionate C. Mercuric chloride D. Copper sulfate
Sodium nitrate
True/ False Bacteria are to large to pass through a filter and are retained on it.
True
True/ False Heating is the most common use for killing microbes
True
A nurse is working in southeast Asia, where the incidence of Mycobacterium tuberculosis is very high. Why is it necessary to select a specific method of disinfection for this organism ? A. The presence of a capsule makes this organism more resistant to disinfectants. B. Bacterial endospores made by this organism are resistant to disinfectants. C. The presence of an envelope makes this organism relatively resistant to disinfectants. D. The waxy, lipid-rich components of the cell wall make this organism relatively resistant to disinfectants.
The waxy, lipid-rich components of the cell wall make this organism relatively resistant to disinfectants
The lowest temp at which all microorganisms in a particular liquid suspension will be killed in 10 minutes A. Decimal reduction time B. Thermal death time C. Thermal death point
Thermal death point
MInimal length of time for all bacteria in a particular liquid culture to be killed at a given temp will be killed A. Decimal reduction time B. Thermal death time C. Thermal death point
Thermal death time
What is required to affect more resistant microbes or endospores A. Time of exposure B. Environment C. bacteriostasis D. filtration
Time of exposure
The main effect of cold treatment is to A. kill pathogenic microbes B. To sterilize an item C. To slow microbial growth D. To destroy vegetative cells
To slow microbial growth
Can be found in household antibacterial soaps A. Triclosan B. Chlorine C. Hexachlorophene (pHisoHex) D. Chlorhexidine
Triclosan
Effective against most bacteria and fungi A. Triclosan B. Chlorine C. Hexachlorophene (pHisoHex) D. Chlorhexidine
Triclosan
________ is a compound found in antimicrobial soaps that targets gram-positive bacteria. A. Sodium nitrate B. Mercuric chloride C. Formaldehyde D. Triclosan E. Hydrogen peroxide
Triclosan
True/ False Mycobacteria, endo spores and protozoan cysts are very resistant to disinfectants and antispetics
True
What are resistant to desiccation A. Molds and yeast B. Viruses C. bacteria
Viruses
Chlorine
a common nonmetallic element belonging to the halogens, forms hypochlorous acid(HOCI) when added to water. Works by inactivating enzyme systems.
sepsis
a condition in which pathogenic microorganisms, usually bacteria, enter the bloodstream, causing a systemic inflammatory response to the infection
peracetic acid
a liquid sterilant used to disinfect food-processing and medical equipment
bacteriostasis
a method or agent which inhibits microbial growth
equivalent treatments
as temp increases, much less time is needed to kill the same number of organisms
Object or area is free of pathogens, absence of significant contamination A. Biocides B. aspetic C. virucide D. bacteriostasis E. spesis
aspetic
oligodynamic action
ability of very small amounts of heavy metals, especially silver and copper, to exert antimicrobial activity
asepsis
absence of significant contamination, aseptic surgery techniques prevent microbial contamination of wounds
desiccation
absence of water prevents metabolism, but can remain viable for years, resume growth when water is made available
chemical agents action
affected by concentration of disinfectant, organic matter, pH, direct contact, time
Which of the following pairs is mismatched? A. organic acids food preservation B. H2O2 open wounds C. alcohols open wounds D. Ag wound dressings E. CuSO4 algicide
alcohols open wounds
chlorine
also a halogen, bleach- hypochlorous acid, oxidizing agent, prevents cellular enzymes from functioning, used for disinfecting drinking water, swimming pools and sewage
actions of microbial control agents
alteration of membrane permeability, damage to protien (enzyme), damage to nucleic acids (replicate, metabolic functions)
way to kill microbes
alteration of membrane permeabiltity
high pressure
alters molecular structure of carbohydrates and protiens, preserves color, flavor and nutrient value of fruit juices
Oxidizing agents, such as hydrogen peroxide, are useful for irrigating deep wounds where released oxygen will inhibit the growth of __________.
anaerobic bacteria
The chemical disinfection of living tissue is known as A) antisepsis B) degerming
antisepsis Antisepsis is the chemical disinfection of living tissues
halogen
any of five related nonmetallic elements (fluorine or chlorine or bromine or iodine or astatine) that are all monovalent and readily form negative ions
surfactant
any substance that interferes with the hydrogen bonding between water molecules and thereby reduces surface tension
Which method achieves sterilization? A) pasteurization B) the autoclave
autoclave The autoclave uses heat under pressure to allow temperatures above the boiling point of water to be reached.
Which of the following treatments achieves sterilization? A. pasteurization B. freezing C. bringing water to a boil D. autoclaving
autoclaving Autoclaving destroys all living organisms, spores, and endospores, thereby sterilizing heat-stable items
Treatments that inhibit the growth and multiplication of bacteria A. sterilization B. bacteriostasis C. Disinfection D. Degerming E. Sanitization
bacteriostasis
Some antimicrobial treatments kill microbes; some inhibit growth. Which term refers to an agent that inhibits bacterial growth? A. germicidal B. bacteriostatic C. homeostatic D. fungicidal E. bacteriocidal
bacteriostatic
Which of the following pairs of terms is mismatched? A. virucide - inactivates viruses B. fungicide kills yeasts and molds C. sterilant destroys all living microorganisms D. bacteriostatic kills vegetative bacterial cells E. germicide - kills microbes
bacteriostatic kills vegetative bacterial cells
All of the following are examples of microbial control using heavy metals except ________. A. mouthwash solution containing zinc chloride. B. burn treatment using silver-sulfadiazine ointment C. algae control in swimming pools using copper sulfate D. benzoyl peroxide used for acne treatment E. antiseptic solution containing mercurochrome
benzoyl peroxide used for acne treatment
chemical type used for controling microbes
biguanides: - chlorhexidine, used on skin and mucous membranes - does not kill mycobacteria, endospres,prtozoan cysts, and some viruses - blocks enzyme needed for lipid sythesis(interfering with plasma membrane)
What group of chemicals does triclosan fall into? A) a halogen B) a bisphenol
bisphenol Triclosan is a bisphenol found in many antimicrobial products, including antibacterial soaps
Which of the following disinfectants acts by disrupting the plasma membrane? A. heavy metals B. halogens C. bisphenols D. soaps E. aldehydes
bisphenols
__________ is a common household disinfectant that has been used to disinfectant everything from dairies to drinking water.
bleach
Can kill vegetative forms of bacterial pathogens, but does not kill virueses and endospores A. boiling B. Autoclaving C. pasteurization D. Dry heat sterilization
boiling
Not a reliable sterilization procedure A. boiling B. Autoclaving C. pasteurization D. Dry heat sterilization
boiling
Some hepatitis viruses can survive up to 30 minutes of A. boiling B. Autoclaving C. pasteurization D. Dry heat sterilization
boiling
Useful to sanitize glass A. boiling B. Autoclaving C. pasteurization D. Dry heat sterilization
boiling
moist heat
boiling(100C) kills most microbes within minutes but ineffective against endospores and some viruses
biguinides
broad spectrum of activity, disrupts plasma membrane, effective on gram + and some gram - bacteria, some effectiveness against enveloped virus; chlorohexidine used for microbial control on skin and mucous membranes-surgical hand scrub
How does alcohol kill bacteria? A) by denaturing proteins B) by inhibiting DNA synthesis
by denaturing proteins
chemical methods
can control microbes on living tissue and inanimate objects; few achieve sterility; agent selection in a common problem (read label)
Refrigeration has a bacteriostatic effect on most microbes so they A. grow farily well B. will not grow at all C. cannot reproduce or make toxins
cannot reproduce or make toxins
bacteriocidal
capable of killing bacteria. Antibiotics, antiseptics, and disinfectants can be bactericidal.
phenol
carbolic acid, Lister used to control surgical infections in the operating room; rarely used today because of odor and irritates the skin
osmotic pressure
cause plasmolysis, high concentration of sugar or salt creates hypertonic environment
mycobacteria
cell wall has waxy lipid-rich component and exhibit greater than normal resisitance
organic acids
chemical preservative inhibits metabolism, sorbic acid and sodium benzoate prevent mold from growing on surface of foods
chloramine
chlorime and ammonia, chlor-floc clarifies water; sanitize glassware, eating utensils and dairy equipment
Which one of the following substances is effective against bacterial endospores? A. bisphenols B. quaternary compounds C. mercury D. chlorine
chlorine
Which one of these halogen compounds would be considered an antiseptic? A. hypochlorous acid B. calcium hypochlorite C. chlorine dioxide D. chlorine gas
chlorine dioxide
iodophor
combined with an organic molecule, from which the iodine is released slowly; Betadine for skin disinfection and wound treatment
way to kill microbes
damage to proteins
Application of heat to living cells can result in all of the following EXCEPT A. alteration of membrane permeability. B. denaturation of enzymes. C. decreased thermal death time. D. damage to nucleic acids. E. breaking of hydrogen bonds
decreased thermal death time
physical type used for controling microbes
deep freeze: (-50 to -95C) formation of ice crystals will kill some and die at a slow rate.
What is removal of microbes from skin by mechanical cleansing or by an antiseptic called? A) sanitization B) degerming
degerming Degerming removes microbes from the skin, such as when an alcohol swab is used prior to an injection.
Moist heat kills microbes by __________ of cellular components
denaturation
This effect is produced by the action of heavy sulfhydryl groups on cellular proteins A. emulsification B. denaturation
denaturation
Why is water needed to make alcohol more effective
denaturation
The preservation of beef jerky from microbial growth relies on which method of microbial control? A. filtration B. lyophilization C. desiccation D. supercritical CO2 E. ionizing radiation
desiccation
physical type used for controling microbes
desiccation: -removes water - bacteriostatic -often combined with another method to control microbes
Sterilization is the ________. A. destruction of all life-forms B. destruction of all forms of microbial life except endospores C. effective removal of all microbes on a surface D. control of all microbial growth E. same as sanitization
destruction of all life-forms
All of the following methods are used for food preservation except ________. A. dessication B. osmotic pressure C. direct flaming D. deep freezing E. commercial canning
direct flaming
dry heat
direct flaming, incineration, hot air; requires a longer period at higher temperatures
Disk-diffusion method
disk or filter paper soaked in disinfectant, placed on agar plate previosly inoculated and incubated
physical type used for controling microbes
dry heat: 1.incineration, 2. hot air method at 170C for 2 hrs.
acid-anionic sanitizer
effectivness related to the negative anion reacting with the plasma membrane of a wide spectrum of organisms, nontoxic, non corrosive and fast acting; cleaning dairy equipment and utensils
radiation
effects on cells depend on wavelength, intesity and duration
What is the best definition of sterilization? A. removal of unwanted microorganisms B. removal of viruses C. elimination of bacteria D. elimination of all microorganisms
elimination of all microorganisms
Break down of oily film into tiny droplets A. emulsification B. denaturation
emulsification
QUATS do Not kill A. fungus B. endospores C. enveloped viruses
endospores
Which of the following chemical agents is used for sterilization? A. phenolics B. ethylene oxide C. alcohol D. soap E. chlorine
ethylene oxide
Which one of these chemical treatments kills cells by causing cross-linking of nucleic acids and proteins and inhibits vital cellular functions? A. alcohol B. ethylene oxide C. heavy metals D. soaps and detergents
ethylene oxide
True/False Household bleach contains chlorhexidine as the active ingredient
false
physical type used for controling microbes
filtration: separation of microbes from a gas or liquid by passing through a screen-like material small enough to retain microorganisms
Which of the following is not a major target for action of antimicrobials? A. proteins B. nucleic acids C. enzymes D. cell membranes E. flagella
flagella
Process of sterilizing an inoculating loop by holding it in an open flame A. Hot-air sterilization B. High-temp short-time (HTST) pasteurization C. flaming D. ultra-high temp treatment (UHT)
flaming
Used by morticians for embalming A. formaldehyde B. hexachlorophene C. Chlorhexidine D. Chlorine
formaldehyde
Used to preserve biological specimens A. formaldehyde B. hexachlorophene C. Chlorhexidine D. Chlorine
formaldehyde
plasma
free radicals destroy even endospore forming microbes; in a container plasma is formed by vacuum, electromagnetic field and chemicals, only requires low temperatures, is expensive; used for tubular instruments
A chemical that reduces spoilage in fruit by destroying fungi, but does not appear to affect other microbes, would be called a __________. A. fungicidal agent B. fungistatic agent C. sterilant D. bactericidal agent
fungicidal agent
Kills fungus A. Biocides B. fungicides C. virucide D. bacteriostasis E. spesis
fungicides
Which one of these products is most useful for disinfecting medical instruments? A. iodine B. glutaraldehyde C. alcohols D. soap and detergents
glutaraldehyde
What are more resistant to disinfectants and antiseptics A. gram-negative bacteria B. gram-positve bacteria C. viruses D. mold and fungi
gram-negative bacteria
Psychrotrophs _______ at refrigerator temps A. grow farily well B. will not grow at all C. cannot reproduce or make toxins
grow farily well
What is more effective under acidic conditions A. heat B. UV radiation C. chemicals D. gases
heat
thermoduric
heat resistant bacteria that survive pasteurization, but are unlikely to cause disease or spoilage
Which of the following results in lethal damage to nucleic acids? A. heat B. radiation C. certain chemicals D. heat and radiation E. heat, radiation, and some chemicals
heat, radiation, and some chemicals
peroxygens
hydrogen peroxide, not good for open wounds, food industry for aseptic packaging, disinfect inanimate objects; benzoyl peroxide for over the counter acne treatment
tinctures
in a solution of aqueous alcohol
aldehydes
inactivates by crosslinking with a functional group; formaldehyde (formalin) preserves biological specimens and inactivates bacteria and viruses in vaccines; glutaraldehyde used for endoscopes- cidex, bactericidal, chemical sterilizing agent
Which one of the following physical methods of microbial control is bactericidal? A. refrigeration B. deep-freezing C. desiccation D. incineration
incineration
prions
infectious protien that causes neurological diseases (spongiform encephalopathies); animal carcasses are incinerated, surgical instruments are autoclaved at 134 degree, use protease enzyme or disposabe
bacteriostasis
inhibit the growth and multiplication of bacteria; once agent is removed, growth might resume
lower temperature
inhibits microbial growth; depends on the microbe and intensity of application
autoclave
instrument for sterilization by means moist heat under pressure
halogens
iodine- effective against bacteria, endospores, fungi and some virus; water treatment for campers; alters protien synthesis and membranes
When iodine is combined with an organic molecule, it is called A) an iodophor B) tincture
iodophor When iodine is combined with an organic molecule, it is called an iodophor.
rate of bacterial death
is usually constant and depends on the number of cells, load
microwaves
kill by heat, not especially antimicrobial
commercial sterilization
killing Clostridium botulinum endospores
moist heat sterilization
killls microorganisms by denaturing protiens
alcohols
kills bacteria and fungi, not endospores and noneveloped virus; denatures protien, dissolves lipids; act evaporate and leave no residue, swabbing skin wipes away dirt, microbes and oil; on wounds cause layer of protien under which bacteria could grow
dry heat
kills by oxidation effects. (ex: incineration, hot-air)
boiling
kills in +/- 10 minutes vegetative forms of bacterial pathogens, almost all viruses, fungi and their spores
biocide/germicide
kills microbes
nonionizing radiation
longer wavelengths, uv light, germicidal lamps in nurseries, hospital rooms, operating rooms, cafeterias; can damage eyes
physical type used for controling microbes
low temp: inhibits growth by decreasing the rate of chemical reactions in a cell. Used as a preservation method.
sanitization
lowering microbial counts on eating utensils
thermal death point TDP
lowest temperature at which all cells in a culture are killed in 10 minutes
physical type used for controling microbes
lyophilization: cells are quickly frozen, dehydrated and cells can remain viable for years
degerming
mechanical removal of micro organizisms
Which of the following is the best method to sterilize heat-labile solutions? A. dry heat B. autoclave C. pasteurization D. freezing E. membrane filtration
membrane filtration
Most pathogenic bacteria are A. mesophilic B. psychotrophic C. thermophilic
mesophilic
What is the typical mechanism of action for chemical food preservatives? A. oxidation B. surface-active agents for removal of microbes C. metabolic inhibition D. disruption of plasma membranes
metabolic inhibition
Use-Dillution tests
metal rings are dipped in bacteria and dried, cultures are placed in disinfectant for 10 minutes at 20 degrees, rings are tranferred to culture medium
Which type of radiation is least effective in killing microbes? A. gamma rays B. microwaves C. x-rays D. high-energy electron beams E. ultraviolet rays
microwaves
decimal reduction time DRT
minutes to kill 90% of a population at a given temperature
physical type used for controling microbes
moist heat: 1.boiling, 2. Autoclaving
prions
most resistant microbes, virus-like particles, only protein, NO DNA OR RNA
antibiotics
nisin and natamycin prevent spoilage of cheese
Which are generally more resistant to disinfectants A. nonenveloped viruses B. enveloped viruses
nonenveloped viruses
Which of the following are NOT typically destroyed by antimicrobial agents? A. nuclei B. proteins C. nucleic acids D. plasma membranes
nuclei Bacteria do not contain nuclei, and since most disinfectants target bacteria, nuclei are not a typical target
effectiveness of antimicrobial treament
number of microbe, environmental influences, time of exposure, microbial characteristics
nitrite
prevents endospore germination
Recently, silver has been considered in new applications for microbial control, such as impregnating surgical dressings and infusing food containers with silver. These new applications are important because silver is__________. A. useful as a surface-active agent B. effective in dissolving lipids in the plasma membrane C. oligodynamic and unaffected by antimicrobial resistance D. effective as an oxidizing agent
oligodynamic and unaffected by antimicrobial resistance
peracetic acid
one of themost effective liquid chemical sporicides, can be used as a sterilant, FDA approved for washing fruits and vegetables
Which method of control is it when we use concentrated salt solutions to cure meats? A) osmotic pressure B) high pressure
osmotic pressure
physical type used for controling microbes
osmotic pressure: causes loss of water from cells by creating a hypertonic enviorment, bacteriostatic
The purpose of this method to control microbial growth is to eliminate pathogenic microbes and reduce microbial numbers A. boiling B. Autoclaving C. pasteurization D. Dry heat sterilization
pasteurization
This process gives the product a longer shelf life A. boiling B. Autoclaving C. pasteurization D. Dry heat sterilization
pasteurization
Which of the following does not kill endospores? A) autoclaving B) pasteurization
pasteurization Pasteurization does not kill endospores
physical type used for controling microbes
pasteurization: the process of treating a substance with heat to destroy or slow the growth of pathogens. Does not sterilize material.
bisphenol
phenol deririvites; hexachlorophene used for surgical and hospital microbial control, gram + strep and staph; Triclosan used in soap, toothpaste affect plasma membrane, widespread use and resistant bacteria being reported
phenolics
phenol derivities have lower irritating qualities and higher antimicrobial qualities; attacks lipid membrane; suitable for disinfecting pus, saliva and feces; cresol is derived from coal tar and ingredient in lysol
Is the target of many microbial control agents A. cell wall B. plasma membrane C. Enzymes D. Nucleic acid
plasma membrane
What regulates the passage of nutrients into the cell and eliminates waste A. cell wall B. plasma membrane C. Enzymes D. Nucleic acid
plasma membrane
Which of the following infectious agents challenges current sterilization strategies that have been accepted and in use for decades? A. endospores B. mycobacteria C. HIV D. methicillin-resistant Staphylococcus aureus (MRSA) E. prions
prions
Which of the following is least likely to be damaged by exposure to gamma radiation? A. protozoa B. prions C. bacteria D. fungi E. viruses
prions
Disinfection methods have NOT completely solved the problem of destroying which of the following? A. prions B. endospores C. protozoan cysts D. enveloped viruses
prions Prions are especially difficult to destroy. Incineration has been used for infected organisms. but effective treatment for equipment is still being determined. Even autoclaving requires the addition of sodium hydroxide.
Which of these microbes is the most difficult to destroy using either chemical or physical methods? A. prions B. HIV C. MRSA (methicillin-resistant Staphylococcus aureus) D. bacterial endospores
prions Prions are the most difficult infectious particles to destroy. Currently, a combination of very high temperature and sodium hydroxide is used
Moist heat kills cells by denaturing their A. plasma membrane B. cell wall C. proteins D. nuclei
proteins
ethanol
pure is less effective than mixed with water; ingredient in purell
quats
quaternary ammonium compounds; cationic detergent, strong bactericidal against gram + organisms, not mycobacteria or endospores, most widely used surface acting sanitizer; brands are Zephiran and Cepacol, colorless odorless, stabel easily diluted, notoxic at low concentrations
sepsis
refers to microbial contamination
physical type used for controling microbes
refigeration: (0-70C) psychrotrophs can grow but most pathogens genreally will not
gram negative bacteria
relative resistance to biocides, external lipopolysaccharide layer, pseudomonas and burholderia can grow in some antibiotics; resistant due to porin characteristics
sterilization
remaval of all microbial life
Which of the following correctly describes antisepsis? A. destruction of vegetative microorganisms on inanimate surfaces B. removal of vegetative microorganisms from living tissue C. reduction of microbial cells on eating or drinking utensils D. destruction of all organisms on any surface
removal of vegetative microorganisms from living tissue
degerming
removing microbes from a limited area, mostly mechanical removal
disinfect
removing non-endospore forming pathogens, not equal to sterilization, usually a chemical on an inert surface
antisepsis
removing pathogens from living tissue; often a chemical
Which type of treatment is it when a restaurant washes its eating utensils? A) sanitization B) degerming
sanitization Sanitization lowers the microbial count to safe public health levels
filtration
separation of microbes from a gas or liquid by passing through a screen-like material small enough to retain microorganisms
ionizing radiation
shorter wavelength carries more energy, damages DNA, low level for some foods, high energy to sterilize pharmaceuticals and disposable medical and dental supplies
Ag, Hg and Cu
silver for surgical dressing and topical cream, murcury in paints, copper as algicide- metals used as antimicrobials
Used as a topical cream for use on burns A. silver-sulfadiazine B. Mercuric chloride C. Copper sulfate
silver-sulfadiazine
An antiseptic is used to remove microbes from ________. A. restaurant glassware B. food preparation areas C. toilet surfaces D. skin, before an injection E. foods, before canning them
skin, before an injection
isopropanol
slightly superior to to ethanol as antiseptic/disinfectant, less expensive, less volatile
What is the main effect of refrigeration on microbes? A) kills microbes B) slows microbial growth
slows microbial growth
surface acting agents
soap (degerming); acid anionic detergent (sanitizing); Quat (cationic detergent-bactericidal, denatures protien)
The decay or putrid, indicates bacterial contamination A. Biocides B. aspetic C. virucide D. bacteriostasis E. spesis
spesis
Food is subjected to enough heat to destroy the endospores A. sterilization B. Antisepsis C. Disinfection D. Degerming E. Sanitization
sterilization
The destruction or removal of all forms of life A. sterilization B. Antisepsis C. Disinfection D. Degerming E. Sanitization
sterilization
Usually done by steam under pressure or ethylene oxide A. sterilization B. Antisepsis C. Disinfection D. Degerming E. Sanitization
sterilization
Destroying all forms of microbial life is known as A) disinfection B) sterilization
sterilization Sterilization is the destruction of all forms of microbial life
What would be an appropriate use of ultra-high-temperature treatment? A) sterilizing rubber tubing B) sterilizing coffee creamers.
sterilizing coffee creamers
gasous chemosterilants
substitute for physical sterilization, denatures protiens and used on heat sensitive materials; ethylene oxide- kills microbes and endospores at ambient temperatures, highly penetrating (mattresses can be sterilized), toxic and explosive in pure form
ozone
supplements chlorine disinfection of water, neutralizes tastes and odor
surfactants
surface acting agents, decrease surface tension among molecules of a liquid- soaps and detergents; mechanical removal of microbes
chemical type used for controling microbes
surfactants: soap,and detergents decrease surface tension among molecules in a liquid.
What does UV radiation damage in a cell? A) proteins B) the DNA
the DNA
What makes mycobacterium susceptible to phenolics A. the cell wall B. the plasma mebrane C. nucleic acid D. ribosomes
the cell wall
Pasteurized milk in an unopened container spoils in the refrigerator. A sample reveals the presence of microorganisms. The most likely explanation is ________. A. the microbes that survived pasteurization were able to grow at 4°C. B. the microbes are pathogens C. the pasteurization process was ineffective D. a leak in the milk carton allowed microbes to enter E. pasteurization-resistant mutants developed after pasteurization
the microbes that survived pasteurization were able to grow at 4°C.
sterilization
the procedure of making some object free of live bacteria or other microorganisms (usually by heat or chemical means)
pasteurization
the process of treating a substance with heat to destroy or slow the growth of pathogens. Does not sterilize material.
Which of these is not a characteristic of the autoclave? A. the use of moist heat B. the requirement for long (hours) exposure times C. the ability to sterilize solutions with endospores D. the use of high temperatures E. the use of high pressures
the requirement for long (hours) exposure times
WHat happens to vegetative cells when the pressure is high A. the vegetative cells become deystroyed, rapidly B. the vegetative cells grow slowly over a longer period of time C. the vegetative cells multiply at a faster rate
the vegetative cells become deystroyed, rapidly
thermal death time TDT
time taken to kill al cells in a culture at a specific temperature
Hydrogen peroxide is best used A. as a antiseptic for open wounds B. to disinfect inanimate objects C. To clean a surgical site D. To kill prions
to disinfect inanimate objects
For which of the following would it be appropriate to use high-energy electron beams as a means to control microbial growth? A) to sterilize disposable dental supplies B) to disinfect the air going into a nursery
to sterilize disposable dental supplies
disinfection
treatment to destroy harmful microorganisms
Which of these chemicals inhibits an enzyme required for synthesis of membrane lipids? A. chlorine B. hydrogen peroxide C. ozone D. triclosan
triclosan
True/False The most commonly used iodophor is Betadine
true
A method of treating food with high temps for very short times to make the food sterile so that it can be stored at room temp. A. Hot-air sterilization B. High-temp short-time (HTST) pasteurization C. flaming D. ultra-high temp treatment (UHT)
ultra-high temp treatment (UHT)
Packages of milk and coffee creamers may be stored without refrigeration if they have been sterilized by ________. A. boiling B. ultra-high-temperature (UHT) treatment C. autoclaving D. treatment with phenol E. high-temperature short-time (HTST) pasteurization
ultra-high-temperature (UHT) treatment
moist heat sterilization
used for sterilization culture media, instruments, dressings, intravenous equipment, applicators, solutions, syringes, etc steam must contact all surfaces
sodium nitrite
used in meat products to prevent the growth of C. bolulinum
Inactivates viruses A. Biocides B. fungicides C. virucide D. bacteriostasis E. spesis
virucide
For control of microbial growth on a surface, which of these conditions is LEAST likely to interfere with the effectiveness of an antiseptic or disinfectant? A. presence of organic matter B. high numbers of microbes C. presence of biofilms D. warm environmental conditions
warm environmental conditions
When would it be appropriate to use glutaraldehyde? A) when embalming corpses B) when disinfecting water for swimming pools
when embalming corpses
Bacteria that are mesophilic _____ at refrigerator temps A. grow farily well B. will not grow at all C. cannot reproduce or make toxins
will not grow at all
Pasteurization was first used by Pasteur to control spoilage of ________. A. milk B. yogurt C. wine D. cheese E. canned foods
wine
The following may be listed on the ingredients of your favorite snack food. Which of these products is not antimicrobial? A. sodium benzoate B. sorbic acid C. xanthan D. potassium sorbate E. calcium propionate
xanthan
During a flood, a community's well water system is contaminated with a pathogenic fungus. If the residents boil their water for 15 minutes prior to consumption, will they be protected? A. yes, most likely B. probably not C. definitely not
yes, most likely