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 |
fungicidal agent |
What is the best definition of sterilization? A. removal of unwanted microorganisms |
elimination of all microorganisms |
Which of the following correctly describes antisepsis? A. destruction of vegetative microorganisms on inanimate surfaces |
removal of vegetative microorganisms from living tissue |
Which of the following treatments achieves sterilization? A. pasteurization |
autoclaving Autoclaving destroys all living organisms, spores, and endospores, thereby sterilizing heat-stable items |
Which one of these halogen compounds would be considered an antiseptic? A. hypochlorous acid |
chlorine dioxide |
Which one of these chemical treatments kills cells by causing cross-linking of nucleic acids and proteins and inhibits vital cellular functions? A. alcohol |
ethylene oxide |
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 |
warm environmental conditions |
Which of the following are NOT typically destroyed by antimicrobial agents? A. nuclei |
nuclei Bacteria do not contain nuclei, and since most disinfectants target bacteria, nuclei are not a typical target |
Which one of the following physical methods of microbial control is bactericidal? A. refrigeration |
incineration |
Which one of the following substances is effective against bacterial endospores? A. bisphenols |
chlorine |
A nurse is degerming a patient’s arm before giving a vaccination. Which of these concentrations of alcohol is most effective? A. 100% |
75% Alcohols work by denaturing proteins, and this process requires water. Generally, the most effective alcohol concentration is 70%. |
Which of these microbes is the most difficult to destroy using either chemical or physical methods? A. prions |
prions Prions are the most difficult infectious particles to destroy. Currently, a combination of very high temperature and sodium hydroxide is used |
Which of these chemicals inhibits an enzyme required for synthesis of membrane lipids? A. chlorine |
triclosan |
Which one of these products is most useful for disinfecting medical instruments? A. iodine |
glutaraldehyde |
What is the typical mechanism of action for chemical food preservatives? A. oxidation |
metabolic inhibition |
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 |
oligodynamic and unaffected by antimicrobial resistance |
Disinfection methods have NOT completely solved the problem of destroying which of the following? A. prions |
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. |
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. |
The waxy, lipid-rich components of the cell wall make this organism relatively resistant to disinfectants |
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 |
UHT treatment Ultra-high-temperature (UHT) is a treatment that essentially sterilizes the product |
True/False Most viruses are highly resistant to disinfectants and antiseptics |
False |
True/False The presence of organic matter, such as blood or saliva, may impair the action of antimicrobial chemicals |
True |
True/False All bacteria die at once when they are exposed to heat or chemical treatment |
False |
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 Ethylene oxide gas is used to sterilize medical equipment that might be damaged by exposure to the heat of autoclaving |
True |
True/False UV radiation and x-ray radiation are similar in that they damage DNA and have a high penetrating power |
False |
True/False Iodine is one of the least effective antimicrobial chemicals, effective only against certain very sensitive strains of bacteria. |
False |
True/False Soap is ineffective in killing bacteria. Therefore, hand washing is a rather ineffective measure in preventing disease transmission. |
False |
True/False Ionizing radiation can be used to sterilize some foods such as spices, meat, and fruits and vegetables. |
True |
Sterilization is the ________. A. destruction of all life-forms |
destruction of all life-forms |
An antiseptic is used to remove microbes from ________. A. restaurant glassware |
skin, before an injection |
Which of the following infectious agents challenges current sterilization strategies that have been accepted and in use for decades? A. endospores |
prions |
Some antimicrobial treatments kill microbes; some inhibit growth. Which term refers to an agent that inhibits bacterial growth? A. germicidal |
bacteriostatic |
Which of the following is not a major target for action of antimicrobials? A. proteins |
flagella |
Which of these is not a characteristic of the autoclave? A. the use of moist heat |
the requirement for long (hours) exposure times |
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. |
the microbes that survived pasteurization were able to grow at 4°C. |
Pasteurization was first used by Pasteur to control spoilage of ________. A. milk |
wine |
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. |
Prepare and autoclave the medium before adding the growth factors. After the medium has cooled, filter sterilize and aseptically add the growth factors. |
Which of the following is least likely to be damaged by exposure to gamma radiation? A. protozoa |
prions |
Packages of milk and coffee creamers may be stored without refrigeration if they have been sterilized by ________. A. boiling |
ultra-high-temperature (UHT) treatment |
All of the following methods are used for food preservation except ________. A. dessication |
direct flaming |
Some microbes are very resistant to antimicrobial chemicals. Which of the following would be the easiest to kill? A. Mycobacterium tuberculosis |
E. coli |
Which type of radiation is least effective in killing microbes? A. gamma rays |
microwaves |
Alcohol is most effective when used as a ________ solution. A. 95% |
70% |
All of the following are examples of microbial control using heavy metals except ________. A. mouthwash solution containing zinc chloride. |
benzoyl peroxide used for acne treatment |
________ is a compound found in antimicrobial soaps that targets gram-positive bacteria. A. Sodium nitrate |
Triclosan |
The following may be listed on the ingredients of your favorite snack food. Which of these products is not antimicrobial? A. sodium benzoate |
xanthan |
The decimal reduction time is the time required to kill __________ percent of a bacterial population |
90% |
Moist heat kills microbes by __________ of cellular components |
denaturation |
__________ is a common household disinfectant that has been used to disinfectant everything from dairies to drinking water. |
bleach |
Oxidizing agents, such as hydrogen peroxide, are useful for irrigating deep wounds where released oxygen will inhibit the growth of __________. |
anaerobic bacteria |
__________ bacteria may survive pasteurization |
Heat resistant |
__________ ammonium compounds are less effective against gram-negative bacteria and more effective against gram-positive bacteria. |
Quaternary |
What is removal of microbes from skin by mechanical cleansing or by an antiseptic called? A) sanitization |
degerming Degerming removes microbes from the skin, such as when an alcohol swab is used prior to an injection. |
Destroying all forms of microbial life is known as A) disinfection |
sterilization Sterilization is the destruction of all forms of microbial life |
The chemical disinfection of living tissue is known as A) antisepsis |
antisepsis Antisepsis is the chemical disinfection of living tissues |
When iodine is combined with an organic molecule, it is called A) an iodophor |
iodophor When iodine is combined with an organic molecule, it is called an iodophor. |
What group of chemicals does triclosan fall into? A) a halogen |
bisphenol Triclosan is a bisphenol found in many antimicrobial products, including antibacterial soaps |
Which method achieves sterilization? A) pasteurization |
autoclave The autoclave uses heat under pressure to allow temperatures above the boiling point of water to be reached. |
Which type of treatment is it when a restaurant washes its eating utensils? A) sanitization |
sanitization Sanitization lowers the microbial count to safe public health levels |
Which of the following does not kill endospores? A) autoclaving |
pasteurization Pasteurization does not kill endospores |
What does UV radiation damage in a cell? A) proteins |
the DNA |
What would be an appropriate use of ultra-high-temperature treatment? A) sterilizing rubber tubing |
sterilizing coffee creamers |
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 |
to sterilize disposable dental supplies |
How does alcohol kill bacteria? A) by denaturing proteins |
by denaturing proteins |
True/False Household bleach contains chlorhexidine as the active ingredient |
false |
What is the main effect of refrigeration on microbes? A) kills microbes |
slows microbial growth |
When would it be appropriate to use glutaraldehyde? A) when embalming corpses |
when embalming corpses |
True/False The most commonly used iodophor is Betadine |
true |
Which method of control is it when we use concentrated salt solutions to cure meats? A) osmotic pressure |
osmotic pressure |
To which category do iodine and chlorine belong? A) biguanide |
halogen |
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. |
Answers A and B are both correct |
Why would filter sterilization be used rather than heat, such as autoclaving? A. Filter sterilization is less expensive than autoclaving. |
Filter sterilization is used when the contents of the liquid could be harmed by heat |
Which of the following shows the moist heat methods in order of the temperature used (highest to lowest)? A. Ultrahigh>Boiling>Autoclave>Batch Pasteurization |
Ultrahigh>Autoclave>Boiling>Batch Pasteurization |
_______________ 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 |
Pasteurization; the taste of the food or drink will not be altered |
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 |
yes, most likely |
Which of the following chemical agents is used for sterilization? A. phenolics |
ethylene oxide |
Which of the following is the best method to sterilize heat-labile solutions? A. dry heat |
membrane filtration |
Which of the following pairs of terms is mismatched? A. virucide – inactivates viruses |
bacteriostatic kills vegetative bacterial cells |
Which of the following is a limitation of the autoclave? A. It requires an excessively long time to achieve sterilization. |
It cannot be used with heat-labile materials |
Application of heat to living cells can result in all of the following EXCEPT A. alteration of membrane permeability. |
decreased thermal death time |
Which of the following disinfectants acts by disrupting the plasma membrane? A. heavy metals |
bisphenols |
Which concentration of ethanol is the most effective bactericide? A. 100% |
70% |
Which of the following pairs is mismatched? A. organic acids food preservation |
alcohols open wounds |
Which of the following results in lethal damage to nucleic acids? A. heat |
heat, radiation, and some chemicals |
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. |
The preservation of beef jerky from microbial growth relies on which method of microbial control? A. filtration |
desiccation |
True/ False Microorganisms placed in high concentrations of salts and sugars undergo lysis. |
False |
True/ False The pH of the medium has no effect on the activity of the disinfectant being applied. |
False |
True/ False Pseudomonas has been found growing in quaternary ammonium compounds (quats). |
True |
The destruction or removal of all forms of life A. sterilization |
sterilization |
The destruction of vegetative pathogens that do not form endospores A. sterilization |
Disinfection |
Treatment is directed at living tissue A. sterilization |
Antisepsis |
The mechanical removal of most microbes in an area A. sterilization |
Degerming |
Treatment intended to lower microbial counts on eatting and drinking utensils to safe public health levels A. sterilization |
Sanitization |
Usually done by steam under pressure or ethylene oxide A. sterilization |
sterilization |
True/ False Heating is the most common use for killing microbes |
True |
When skin is cleaned with alcohol prior to an injection A. sterilization |
Degerming |
When a restaurant washes its dishes in a high-temp dishwasher A. sterilization |
Sanitization |
Food is subjected to enough heat to destroy the endospores A. sterilization |
sterilization |
Kills microorganisms A. Biocides |
Biocides |
Kills fungus A. Biocides |
fungicides |
Inactivates viruses A. Biocides |
virucide |
Treatments that inhibit the growth and multiplication of bacteria A. sterilization |
bacteriostasis |
The decay or putrid, indicates bacterial contamination A. Biocides |
spesis |
Object or area is free of pathogens, absence of significant contamination A. Biocides |
aspetic |
True/False Aspetic technique is important in surgery to minimize contamination |
True |
True/ False The more microbes there are to begin with, the longer it takes to eliminate the entire population |
True |
True/False The presence of organic matter does not inhibit the action of chemical antimicrobials |
False |
True/False Disinfectants work better under colder temps |
False They work better under warm temps |
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 |
What affects the choice of chemical and physical control methods A. Time of exposure |
Microbial characteristics |
What is required to affect more resistant microbes or endospores A. Time of exposure |
Time of exposure |
What is more effective under acidic conditions A. heat |
heat |
What regulates the passage of nutrients into the cell and eliminates waste A. cell wall |
plasma membrane |
Is the target of many microbial control agents A. cell wall |
plasma membrane |
What are vital to cellular activity A. cell wall |
Enzymes |
Cells can no longer replicate, nor can it carry out normal metabolic functions if there is damage to what A. cell wall |
Nucleic acid |
Can kill vegetative forms of bacterial pathogens, but does not kill virueses and endospores A. boiling |
boiling |
Not a reliable sterilization procedure A. boiling |
boiling |
Useful to sanitize glass A. boiling |
boiling |
Best way to sterilize A. boiling |
Autoclaving |
Used in hospital environments to sterilize equipment A. boiling |
Autoclaving |
True/ False Steam under pressure fails to sterilize when the air is not completely exhausted |
True |
The lowest temp at which all microorganisms in a particular liquid suspension will be killed in 10 minutes A. Decimal reduction time |
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 |
Thermal death time |
The time in minutes, in which 90% of the population of bacteria at a given temp will be killed A. Decimal reduction time |
Decimal reduction time |
Temp must be above 100 degree celsius in order to kill all forms of life. A. boiling |
Autoclaving |
The purpose of this method to control microbial growth is to eliminate pathogenic microbes and reduce microbial numbers A. boiling |
pasteurization |
This process gives the product a longer shelf life A. boiling |
pasteurization |
True/False When milk is pasteurized it is made sterile |
False |
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 |
ultra-high temp treatment (UHT) |
Pasteurizing at 72C for 15minutes to kill pathogens as well lowers total bacterial counts A. Hot-air sterilization |
High-temp short-time (HTST) pasteurization |
Process of sterilizing an inoculating loop by holding it in an open flame A. Hot-air sterilization |
flaming |
Sterilization by the use of an oven at 170C for 2hours A. Hot-air sterilization |
Hot-air sterilization |
Kills by oxidation effects A. boiling |
Dry heat sterilization |
This is used to sterilize heat-sensitive materials, such as culture media, enzymes, vaccines and antibiotic solutions A. Low Temps |
Filtration |
True/ False Bacteria are to large to pass through a filter and are retained on it. |
True |
True/False HEPA filters are used to remove microorganisms from the air |
True |
What type of filter is when a sample needs to be sterilized. A. Membrane filter |
Membrane filter |
Which filter is used to remove microorganisms from the air A. Membrane filter |
HEPA filter |
The main effect of cold treatment is to A. kill pathogenic microbes |
To slow microbial growth |
Most pathogenic bacteria are A. mesophilic |
mesophilic |
Refrigeration has a bacteriostatic effect on most microbes so they A. grow farily well |
cannot reproduce or make toxins |
Psychrotrophs _______ at refrigerator temps A. grow farily well |
grow farily well |
Bacteria that are mesophilic _____ at refrigerator temps A. grow farily well |
will not grow at all |
Advantage of this method is that it preserves the flavors, colors, and nutrient values of products A. Low Temps |
High Pressure |
If the pressure is _____ enough, it alters the molecular structures of proteins and carbohydrates. A. Low |
High |
WHat happens to vegetative cells when the pressure is high A. the vegetative cells become deystroyed, rapidly |
the vegetative cells become deystroyed, rapidly |
This processes uses high concentrations of salts and sugars to cause water to leave cells A. Low Temps |
Osmotic Pressure |
What resists osmotic pressure the most A. vegetative bacteria |
Molds and yeasts |
Ionization of water, which forms highly reactive hydroxyl radicals that damage cellular components A. Radiation |
Radiation |
HIgh energy electron beams are used for the sterilization of pharmaceuticals and disposable dental and medical supplies A. Radiation |
Radiation |
Forms highly reactive hydroxyl radicals that damage cellular components A. Ionizing radiation |
Ionizing radiation |
This type of radiation is used to control microbes in the air, such as in hospital rooms, nurseries, and cafeterias A. Ionizing radiation |
Nonionizing radiation |
Uses gamma rays , X-rays, and high-energy electron beams A. Ionizing radiation |
Ionizing radiation |
Uses UV light A. Ionizing radiation |
Nonionizing radiation |
This process resembles preservation by desiccation, denying it the moisture to grow A. Radiation |
Osmotic pressure |
What are resistant to desiccation A. Molds and yeast |
Viruses |
True/False When water is made available, after desiccation, micrboes can resume their growth and division |
True |
True/ False Most chemical agents achieve sterility |
False Few chemical agents achieve sterility |
This dicinfectant was first used by Joseph Lister to control surgical infections in the OR A. Biphenols |
Phenolics |
Used in throat lozenges A. Biphenols |
Phenolics |
These disinfectant damage to plasma membrane, resulting in leakage of cellular contents A. Biphenols |
Phenolics |
What makes mycobacterium susceptible to phenolics A. the cell wall |
the cell wall |
These disinfectants remain active in the presence of organic material such as pus, saliva, and feces A. Biphenols |
Phenolics |
What is the main ingredient in the product lysol A. Biphenols |
Phenolics |
This bisphenol is used for hospital microbial control during procedures A. Triclosan |
Hexachlorophene (pHisoHex) |
Gram-positive staphylococci and streptococci are susceptible A. Triclosan |
Hexachlorophene (pHisoHex) |
Can be found in household antibacterial soaps A. Triclosan |
Triclosan |
Effective against most bacteria and fungi A. Triclosan |
Triclosan |
Which one is not paired correctly A. Triclosan – Bisphenol |
Chlorine – Alcohol |
This disinfectant damages the plasma membrane of vegetative cells A. Biphenols |
Biguanide |
Effective against gram-positive and gram-negative bacteria except pseudomonads A. Biphenols |
Biguanide |
Triclosan is a member of this group A. Biphenols |
Biphenols |
Chlorhexidine is a member of this group A. Biphenols |
Biguanide |
Hexachlorophene is a member of this group A. Biphenols |
Biphenols |
Iodine is a member of this group A. Biphenols |
Halogens |
Chlorine is a member of this group A. Biphenols |
Halogens |
Formaldehyde is a member of this group A. Biphenols |
Aldehydes |
Glutaraldehyde is a member of this group A. Biphenols |
Aldehydes |
Used in hospital surgical scrubs A. Triclosan |
Chlorhexidine |
When this two components are combined they make Avagard, which is a biguanide A. Iodine and chlorhexidine |
Alcohol and chlorhexidine |
What can be combined with certain amino acids to inactivate enzymes and other cellular proteins A. Alcohol |
Iodine |
What is effective against all kinds of bacteria, many endospores, various fungi, and some viruses A. Triclosan |
Iodine |
Most commonly used in iodophor A. Triclosan |
Betadine |
Used in resin filters for water treatment A. Triclosan |
Iodine |
Can be used for both skin disinfection and wound treatment A. Triclosan |
Betadine |
Widely used disinfectant either as a gas or liquid A. formaldehyde |
Chlorine |
Used to disinfect drinking water, swimming pools and sewage A. formaldehyde |
Chlorine |
Germicidal action, is based on when this disinfectant is added to water to create hypochlorous acid A. formaldehyde |
Chlorine |
What are more resistant to disinfectants and antiseptics A. gram-negative bacteria |
gram-negative bacteria |
True/ False Mycobacteria, endo spores and protozoan cysts are very resistant to disinfectants and antispetics |
True |
Which are generally more resistant to disinfectants A. nonenveloped viruses |
nonenveloped viruses |
What are more resistant to disinfectants and antiseptics A. gram-negative bacteria |
gram-negative bacteria |
True/ False Prions are not resistant to disinfectants and autoclaving |
False |
Effectively kill bacteria and fungi but not endospores and nonenveloped viruses A. Alcohol |
Alcohol |
True/ False One advantage of alcohol is that they act then evaporate rapidly and leave no residue |
True |
Why is water needed to make alcohol more effective |
denaturation |
Which disinfectant exerts their action by denaturing proteins and dissolving lipids A. Alcohol |
Alcohol |
The MOST effective antimicrobial A. Biphenols |
Aldehydes |
Used to preserve biological specimens A. formaldehyde |
formaldehyde |
Used by morticians for embalming A. formaldehyde |
formaldehyde |
Used as a topical cream for use on burns A. silver-sulfadiazine |
silver-sulfadiazine |
inorganic compound that is used as a disinfectant A. silver-sulfadiazine |
Mercuric chloride |
Used to destroy green algae that grows in reservoirs, stock ponds, swimming pools and fish tanks A. silver-sulfadiazine |
Copper sulfate |
True/ False Soap has little value as an antiseptic. It is only used as a mechanical means to remove microbes |
True |
Break down of oily film into tiny droplets A. emulsification |
emulsification |
This effect is produced by the action of heavy sulfhydryl groups on cellular proteins A. emulsification |
denaturation |
Their sanitizing ability is related to the negatively charged portion if the molecule, which reacts with the plasma membrane A. QUATS |
Acid-Anionic Sanitizers |
MOst widely used surface agents, they are related to the positively charged portion of the molecule A. QUATS |
QUATS |
These sanitizers act on thermoduric bacxteria, nontoxic, noncorrosive and fast-acting A. QUATS |
Acid-Anionic Sanitizers |
They are strongly bactericidal, fungicidal, amebicidal, and virucidal against enveloped viruses A. QUATS |
QUATS |
QUATS do Not kill A. fungus |
endospores |
True/False Some species of Pseudomonas not only survive in QUATS but actively grow in them |
True |
Food with a pH of ___ or ____, are most susceptible to spoilage by molds A. 7.0, higher |
5.5, lower |
An effective fungistat used in bread, prevents the growth of surface molds and bacillus bacterium A. Sodium nitrate |
Calcium propionate |
Added to meat products A. Sodium nitrate |
Sodium nitrate |
These organic acids interfer with mold’s metabolism or the integrity of the plasma membrane A. Sodium nitrate |
Calcium propionate |
Prevent germation and growth of any botulism endospores A. Sodium nitrate |
Sodium nitrate |
Nitrate inhibits _____ containing enzymes A. Copper |
Iron |
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 |
Plasma |
This has free radicals that quickly destroy endopore-forming microbes A. Hydrogen Peroxide |
Plasma |
Plasma sterilization requires A. Low Temps |
Low Temps |
True/False Hydrogen peroxide is a good antiseptic for open wounds |
False |
Hydrogen peroxide is best used A. as a antiseptic for open wounds |
to disinfect inanimate objects |
This disinfectant quickly breaks down into water and gaseous oxygen by the action of the enzyme catalase. A. Hydrogen Peroxide |
Hydrogen Peroxide |
One of the most effective liquid chemical sporicides available and can be used as a sterilant A. Hydrogen Peroxide |
Peracetic acid |
A group of oxidizing agents that include hydrogen peroxide and peracetic acid A. Peroxygens |
Peroxygens |
The two microbes most resistant to biocides A. prions |
A. prions B. endospores |
The MOST vulnerable forms of microbes to biocides are: (pick two) A. prions |
C. viruses with lipid envelopes D. gram-positive bacteria |
Moist heat kills cells by denaturing their A. plasma membrane |
proteins |
Some hepatitis viruses can survive up to 30 minutes of A. boiling |
boiling |
Chapter 7-Control of Microbial Growth
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