Chapter 11: Physical & Chemical Control of Microbes
True
True or False: Weak tinctures of heavy metals may be used as antiseptics in intact skin
True
True or false: Halogens are microbicidal and can be sporicidal with longer exposure times
Critical
Blood pressure cuff is
Noncritical
Dental mirror is
False
True or False: There are several degrees of sterility, based on the destruction of endospores
Higher
___ concentrations of alcohol may not have the greatest microbicidal activity, for water is needed for microbial proteins to coagulate
Degermation of skin Disinfection of medical equipment
Alcohols are commonly used for Disinfection of food preparation Degermation of skin Disinfection of drinking water Disinfection of medical equipment Household cleaning
Spores
Alcohols are not effective against naked viruses and bacterial
chemiclave
An ethylene oxide (ETO) is called a(n) ___
Skin wound care Antisepsis of skin
Chlorhexidine solutions are commonly used for Disinfection of drinking water Household cleaning Disinfection of medical equitment Disinfection of food preparation equipment Skin wound care Antisepsis of skin
Bactericidal
Chlorohexidine is reliably
moist; dry
In terms of using heat as an agent of microbial control, ___ heat methods operate at lower temperature and shorter exposure time versus ___ heat methods
Heavy metals
The property of having antimicrobial effects in exceedingly small amounts belongs to which class of chemicals
sporicide
A ___ is an agent that can destroy bacterial endospores
Sterilization
A process that completely removes or destroys all viable microorganisms, including viruses, from an object or habitat is referred to as
iodophor
A(n) ___ is a combination of iodine and an organic carrier (such as alcohol) that serves as a moderate-level disinfectant and antiseptic
Dehydrating cells
Absolute alcohol (100% concentration) inhibits microbial growth by
metals
Although heavy ___ exert potent antimicrobial effects, their risk to human health through toxicity, allergic reactions, and resistance has limited their use in medicine
Fungicide
An agent that kills fungal spores, hyphae and yeasts is called
aqueous; tinctures
Antimicrobial solutions with water as the solvent are called ___ solutions, whereas antimicrobial solutions with alcohol or water-alcohol mixtures as the solvent are called
chemical
Antiseptics are ___ agents applied to the skin to inhibit vegetative bacterial cells
Bacteristatic
Any process or agent that inhibits bacterial growth is referred to as
Microbistatic
Any process or agent that inhibits growth is refereed to as
Swimming pool treatments Food equipment sanitation Household cleaning Wound treatment and skin cleansing
As the most extensively used chlorine compounds, hypochlorites re used for: Swimming pool treatments Sewage and waste water disinfection Food equipment sanitation Household cleaning Wound treatment and skin cleansing
kill
Bactericides ___ bacteria
Disrupting the cell membrane
Cationic detergents typically work by
Enzymes
Chlorine compounds usually kill microbes by denaturing
Disrupting protein function
Chlorine dioxide typically kills microbes by
Materials that can be damaged by heat
Chose the condition under which glutaraldehyde is a good choice for sterilizing materials
human; animal
Disinfectants are normally used only on inanimate objects because they can be toxic or harmful to ___ and ___ tissues
Selective and differential media Staining techniques Chemotherapeutic drugs
Dyes are important for Selective and differential media Identifying contaminated surfaces Staining techniques Genotypic testing Chemotherapeutic drugs
Hydrogen peroxide Peracetic alcohol
Endoscopy equipment becomes highly contaminated with human tissues and fluids, and should be sterilized in low-temperature cabinet using which sterilants Iodine Hydrogen peroxide Chlorine bleach Ethanol Peracetic acid
Blocking DNA replication Disrupting enzyme function
Ethylene oxide typically kills microbes by Blocking DNA replication Producing toxic radicals Inhibiting RNA synthesis Disrupting enzyme function Causing mutations in DNA Disrupting the cell wall
Chlorine
Ethylene oxide, propylene oxide and ___ dioxide are commonly used as gaseous sterilants or disinfectants
Alerting proteins Attaching to nucleic acids
Formaldehyde typically kills microbes by Disrupting the cell membrane Alerting proteins Inhibiting RNA synthesis Attaching to nucleic acids
formaldehyde
Formalin is an aqueous solution of ___ gas that is used as a potent chemical fixative and microbicide
Chlorine
Gaseous and liquid ___ compounds are mostly used for large-scale water disinfection
high
Glutaraldehyde is one of the few chemicals that is officially accepted as a nutrient and ___-level disinfectant
Altering amino acids Disrupting enzyme function
Glutaraldehyde typically kills microbes by Producing toxic radicals Inhibiting RNA synthesis Altering amino acids Disrupting enzyme function
Microbicidal
Heavy metals are reliably
Inactivating Proteins
Heavy metals typically kill microbes by
endospores
High-level germicides can kill ___, whereas intermediate-level germicides can kill fungal spores and resistant pathogens but not endospores
Added to products Clinical disenfection Household disenfection
How are phenolics used in microbial control Added to products Clinical disenfection Household disenfection Routine skin antisepsis
Lysis
If an agent disrupts the cell wall, the cell is likely to experience death by
Treatment of skin wounds Disinfection of medical equipment Emergency disenfection of drinking water Antisepsis of skin
Iodine compounds are commonly used for : Treatment of skin wounds Household cleaning Disinfection of food preparation equipment Disinfection of medical equipment Emergency disenfection of drinking water Antisepsis of skin
Denaturing proteins
Iodine compounds typically kill microbes by
Denaturing proteins Causing mutations in DNA
Lower concentrations of alcohols (50% and higher) usually affect microbes by Denaturing proteins Causing mutations in DNA Disrupting the cell membrane Inhibiting RNA synthesis Inhibiting protein syntheis Disrupting the cell wall
Phenolics
Microbial control agents with the chemical structures illustrated here fall into the category of Heavy metals Acids Phenolics Halogens Detergents
Triclosan
One of the most widely used phenolics used today is
Microbicidal
Phenolics are:
Silver
Pure forms of this metal are currently incorporated into catheter to prevent urinary bladder infections in the hospital
low
Quaternary ammonium compounds are considered to be ___ -level disinfectants
triclosan
Scientists have demonstrated ___ resistance found in organisms, such as E. coli, leads to antibiotic resistance by these organisms
Microbes develop resistance to these metals They can be very toxic to human cells as well as microbial cells
Select which of the following are drawbacks to the use of metals in antimicrobial control methods Microbes develop resistance to these metals They can be very toxic to human cells as well as microbial cells They are not associated with allergic reactions They are still very active in the presence of biological fluids and wastes
Bleach
Sodium hypochloride is also known as
Semicritical
Syringe needle is
phenol; coefficient
The ___ ___ quantitatively compares the effectiveness of a chemical disinfectant to that of phenol
Halogens
The ___ are a group of nonmetallic elements with antimicrobial applications including bromine, iodine, chlorine, and fluorine
Denaturation
The disruption of proteins from their native state is known as
Concentration of germicide Chemical action of a germicide Nature of a microbial population Material being treated Time of exposure to germicide Contamination with organic matter
The effect of a germicide is affected by which of the following factors Concentration of germicide pH of environment Chemical action of a germicide Nature of a microbial population Material being treated Time of exposure to germicide Contamination with organic matter Toxicity to human and animal tissues
Protein function The cell wall The cell membrane Nucleic acid synthesis
The four general cellular targets of antimicrobial agents are: Protein function The cell wall Capsules The cell membrane DNA contained within plasmids Nucleic acid synthesis Extracellular appendages
Oligodynamic
The property of having antimicrobial effects in exceedingly small amounts is called a(n) ___ action
cide
The root- ___ is used to indicate the killing of microorganisms
iodophors
The two primary iodine preparations are free iodine and
Propylene oxide
This gas is safer to use than ethylene oxide to sterilize food products, such as starches, spices, and nuts
False
True or False hydrogen peroxide is used for disenfection of drinking water
False
True or False: 10% alcohol solutions have greater microbicidal activity than 70% solutions
False
True or False: A bactericidal agent will inhibit the growth of bacteria, whereas a bacteristatic agent will kill bacteria
False
True or False: Acids and alkalis are commonly used for drinking water disinfection
False
True or False: Acids or alkalis are limited in their application because they have limited reliability
False
True or False: Alcohol solutions have greater microbicidal activity than 70% solutions
True
True or False: Aldehydes are organic substances that contain a -CHO functional group on a terminal carbon
True
True or False: An agent effect on cells is known as its mode of action
True
True or False: Biological matter such as serum, blood or urine lowers the effectiveness of a germicide
True
True or False: Chlorhexidine solutions are commonly used for skin antisepsis and wound care
True
True or False: Chlorohexidine typically kills microbes by disrupting the cell membrane or denaturing proteins
True
True or False: Glutaraldehyde and formaldehyde are two of the most frequently used aldehydes
False
True or False: Heavy metals are microbistatic
False
True or False: Only a few microorganisms are killed by iodine if proper concentrations and exposure times are used
False
True or False: Phenolics typically kill microbes by inhibiting protein synthesis
True
True or False: Quats are rated for only low-level disenfection in the clinical setting
True
True or False: Silver and mercury are still used in germicidal preparations
True
True or False: Soaps are commonly used for sanitation of the home
True
True or False: The lower temperature that achieves sterilization in a given quantity of broth culture upon a 10-minute exposure is referred to as the thermal death point
True
True or False: The necessity of sterilization or disinfection should be considered when initially choosing a method of microbial control
True
True or False: The primary targets of microbial control are microorganisms that cause in infection or spoilage
True
True or False: Tinctures and ointments are two types of heavy metal germicides
True
True or False:Antimicrobial solutions wit alcohol or water-alcohol mixtures as the solvent are called tinctures
Inactivate
Virucides ___ viruses
200; 1
When a phenolic disinfectant needs to be diluted 1:200, you should mix __ part(s) of water with ___part(s) of the concentrated disinfectant
Oxidizers Halogens Phenolics Aldehydes Alcohols Metals
Which of the following are examples of chemical agents used to control microbes Oxidizers Halogens Phenolics Nitrates Aldehydes Inert gases Alcohols Metals
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?
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?
Soaps can destroy few common hospital pathogens Soaps have great germicidal value when mixed with iodine
Which of the following statements about soaps are correct Soaps can destroy few common hospital pathogens Soaps help to chemically neutralize bacterial contamination Soaps have great germicidal value when mixed with iodine Soaps are strongly microbicidal
OPA does not destroy endospores OPA is effective against viruses
Which of the following statements are NOT correct regarding OPA OPA does not destroy endospores OPA is a detergent OPA is effective against viruses OPA can be irritating to eyes and nasal passages
Ultraviolet rays
Which of the following types is/are types of nonionizing radiation Gamma rays Cathode rays X-rays Ultraviolet rays
Smooth object
Which of the following types of materials can be more reliably disinfected with a germicide
Sterilize respiratory therapy equipment Eliminate hepatitis B viruses on dental equipment Preserve vaccines
Which three of the following are common uses for glutaraldehyde Disinfect skin prior to injecting vaccines Prevent infection in burn patients Retard the growth of molds in bread Sterilize respiratory therapy equipment Eliminate hepatitis B viruses on dental equipment Preserve vaccines
Ethyl Isopropyl
Which two alcohols are effective in microbial control Ethyl Methyl Isopropyl Butyl
Hydrogen peroxide
___ ___ typically kills microbes by producing toxic free radicals
Antiseptics
___ are chemical agents applied directly to body surfaces to inhibit vegetative pathogens
Cationic; anionic
___ detergents are more effective than ___ detergents
Sanitization
___ is a decontamination technique that mechanical removes microorganisms and debris from inanimate objects such as utensils to reduce contamination to safe levels
Soap
___ is an alkaline compound made by combining the fatty acids in oils with sodium or potassium salts
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
broad
___ spectrum action is a desirable characteristic of a germicide