Microbiology- Chapter 11

Chlorhexidine typically kills microbes by: Inhibiting protein synthesis -Denaturing proteins -Disrupting the cell wall -Inhibiting RNA synthesis -Causing mutations in DNA -Disrupting the cell membrane

-Denaturing proteins -Disrupting the cell wall -Disrupting the cell membrane

Phenolics typically kill microbes by: -Disrupting the cell membrane -Denaturing metabolic enzymes -Inhibiting protein synthesis -Causing mutations in DNA -Inhibiting RNA synthesis -Disrupting the cell wall

-Disrupting the cell membrane -Denaturing metabolic enzymes -Disrupting the cell wall

Sterilization is: (select all that apply) -Generally reserved for inanimate objects -Possible for inanimate and animate objects -Always necessary when spores are involved -Only necessary for certain groups of microbes

-Generally reserved for inanimate objects -Only necessary for certain groups of microbes

Which of the following statements about soaps are correct? Soaps are strongly microbicidal. Soaps help to chemically neutralize bacterial contamination. Soaps can destroy few common hospital pathogens. Soaps have great germidical value when mixed with iodine.

-Soaps can destroy few common hospital pathogens. -Soaps have great germidical value when mixed with iodine.

Iodine compounds are commonly used for: Household cleaning Treatment of skin wounds Disinfection of food preparation equipment Antisepsis of skin Disinfection of medical equipment

-Treatment of skin wounds -Antisepsis of skin -Disinfection of medical equipment

Which root indicates the ability to kill microorganisms? -cide -stasis -static

-cide

The primary targets of microbial control are microorganisms that cause ______ or ______. -food spoilage -microbial antagonism -antibiotic production -disease

-food spoilage -disease

Disinfection destroys: -vegetative bacterial cells and endospores -only viruses -only vegetative bacterial cells -only endospores

-only vegetative bacterial cells

Treatment of materials to be sterilized with ethylene oxide in a chemiclave requires about _____.

3 hours

BLANK are organic substances that contain a -CHO functional group on a terminal carbon.

Aldehydes

______ is the destruction of most microbes using chemicals on a living surface such as the skin.

Antisepsis

BLANK are chemical agents applied directly to body surfaces to inhibit vegetative pathogens.

Antiseptics

BLANK is a term referring to a condition free of pathogenic microorganisms or a procedure or process designed to prevent entry of infectious agents.

Asepsis or Aseptic

Chlorohexidine is reliably BLANK

Bactericidal

How are phenolics used in microbial control? Clinical disinfection Added to products Household disinfection Routine skin antisepsis

Clinical disinfection Added to products Household disinfection

A critical concern for the food packaging industry is the elimination of endospores of BLANK Escherichia coli Bacillus anthracis the AIDS virus Clostridium botulinum

Clostridium botulinum

Although they do have some drawbacks, heavy metals are used for: Disinfection of drinking water Disinfection of medical equipment and facilities Controlling microbial growth on objects Preservatives Disinfection of reusable dental equipment Prevention of infection Skin cleansing

Controlling microbial growth on objects Preservatives Prevention of infection Skin cleansing

______ is the physical removal of surface oils, debris, and soil from skin to reduce the microbial load.

Degermation

Alcohol is used in which of the following applications? Disinfection of drinking water Degermation of skin Sterilizing delicate medical instruments Household cleaning

Degermation of skin

Chlorine compounds typically kill microbes by: Disrupting the cell membrane -Inhibiting protein synthesis -Denaturing enzymes -Causing mutations in DNA -Inhibiting RNA synthesis

Denaturing enzymes

BLANK is the use of a physical process or a chemical to destroy vegetative pathogens but not bacterial endospores, usually on inanimate surfaces.

Disinfection

Chlorine dioxide typically kills microbes by:

Disrupting protein function

Cationic detergents typically work by:

Disrupting the cell membrane

Which items can be sanitized by boiling water prior to safe, acceptable use? Drinking water Surgical instruments Utensils Bedding and clothing

Drinking water Utensils Bedding and clothing

Select the statement that most accurately reflects the use of heat as an antimicrobial agent. -Moist heat methods exert their effect by denaturing lipids. -Dry heat methods exert their effect by dehydrating cells. -Moist heat methods require higher temperatures than dry heat methods. -At very high temperatures, moist heat methods oxidize cells to ash.

Dry heat methods exert their effect by dehydrating cells.

Which two alcohols are effective in microbial control?

Ethyl Isopropyl

BLANK oxide is valuable for sterilization of heat-sensitive objects such as plastics, surgical and diagnostic appliances, and spices, but other related gases are available that are less toxic.

Ethylene

Which of the following compounds are commonly used as gaseous sterilants or disinfectants?

Ethylene oxide Propylene oxide Chlorine dioxide

True or false: A process that completely removes or destroys all viable microorganisms, including viruses, from an object or habitat is referred to as disinfection.

False

True or false: Acids or alkalis are limited in their application because they have limited reliability.

False

True or false: Halogens are only microbistatic.

False

True or false: Household cleaners are often alcohol based.

False

True or false: Sepsis is a term referring to a condition free of pathogenic microorganisms or a procedure or process designed to prevent entry of infectious agents.

False

True or false: The phenol coefficient quantitatively compares the effectiveness of a chemical to that of alcohol.

False

True or false: The shortest length of time required to kill all test microbes at a specified temperature is referred to as the thermal death point.

False

True or false: There are several degrees of sterility, based on the destruction of endospores.

False

True or false: A bactericidal agent will inhibit the growth of bacteria, whereas a bacteristatic agent will kill bacteria.

False Reason: Bactericidal agents kill bacteria; bacteristatic agents inhibit the growth of bacteria.

True or false: Only a few microorganisms are killed by iodine even if proper concentrations and exposure times are used.

False.

True or false: Phenolics typically kill microbes by inhibiting protein synthesis.

False.

True or false: Routine skin antisepsis often is completed using phenolics.

False.

True or false: Iodine compounds are commonly used for household cleaning.

False. Reason: Wound and skin cleaning are the main uses of iodine compounds.

BLANK is an aqueous solution of formaldehyde gas that is used as a potent chemical fixative and microbicide.

Formalin

Heavy metals typically kills microbes by:

Inactivating proteins

BLANK are complexes of iodine and alcohol.

Iodophors

Which of the following are disadvantages of OPA as a disinfectant?

OPA does not reliably destroy endospores. It tends to stain proteins, including those in human skin.

Which of the following statements are correct regarding OPA? OPA is not effective against viruses. OPA is an aldehyde. OPA is non-irritating to eyes and nasal passages. OPA can reliably destroy endospores.

OPA is an aldehyde. OPA is non-irritating to eyes and nasal passages.

Which of the following are examples of chemical agents used to control microbes? Oxidizers Inert gases Aldehydes Phenolics Alcohols Heavy metals Halogens

Oxidizers Aldehydes Phenolics Alcohols Heavy metals Halogens

Endoscopy equipment becomes highly contaminated with human tissues and fluids, and should be sterilized in a low-temperature cabinet using which sterilants? Peracetic acid Ethanol Chlorine bleach Iodine Hydrogen peroxide

Peracetic acid Hydrogen peroxide

What factors must be considered in order to adequately sterilize using heat? Presence of water Temperature pH of environment Length of exposure

Presence of water Temperature Length of exposure

Hydrogen peroxide typically kills microbes by:

Producing toxic free radicals

Which of the following are some of the desirable qualities in a germicide? Narrow-spectrum action Rapid action Selective toxicity Penetrating ability Broad-spectrum action Inactivated by organic matter Solubility in a solvent

Rapid action Selective toxicity Penetrating ability Broad-spectrum action Solubility in a solvent

Alcohols are effective against: Naked viruses Bacterial endospores Resistant bacteria Enveloped viruses

Resistant bacteria Enveloped viruses

BLANK is defined as growth of microorganisms in the blood or other tissues.

Sepsis

Chlorhexidine solutions are commonly used for: Skin wound care Disinfection of drinking water Antisepsis of skin Disinfection of food preparation equipment Disinfection of medical equipment Household cleaning

Skin wound care Antisepsis of skin

_____ is an alkaline compound made by combining the fatty acids in oils with sodium or potassium salts.

Soap

Which of the following statements about soaps are correct? Soaps have great germidical value when mixed with heavy metals. Some bacteria can grow on soap as a nutrient source. Soaps are only weakly microbicidal. Soaps help to mechanically remove surface debris. Soaps can destroy most common hospital pathogens.

Some bacteria can grow on soap as a nutrient source. Soaps are only weakly microbicidal. Soaps help to mechanically remove surface debris.

BLANK is the destruction of all microbial life, whereas BLANK destroys most microbial life, thus reducing contamination on inanimate surfaces.

Sterilization; disinfection

Moist heat requires shorter exposure times and lower temperatures than dry heat.

True

True or false: Acids or alkalis are limited in their application by their corrosive and hazardous nature.

True

True or false: Aldehydes are organic substances that contain a -CHO functional group on a terminal carbon.

True

True or false: An agent's effect on cells is known as its mode of action.

True

True or false: An object is either sterile or not sterile.

True

True or false: Boiling water can be an effective means of disinfection in the clinic and home.

True

True or false: Chlorhexidine solutions are commonly used for skin antisepsis and wound care.

True

True or false: Chlorhexidine typically kills microbes by disrupting the cell membrane or denaturing proteins.

True

True or false: Chlorine dioxide disrupts protein function to kill microbes.

True

True or false: Chlorohexidine is bactericidal.

True

True or false: Death involves the permanent termination of a particular organism's vital processes.

True

True or false: Drinking water and utensils are reliably sanitized or disinfected by boiling water.

True

True or false: Halogens and alcohols are examples of chemical agents used to control microbes.

True

True or false: Halogens are microbicidal and can be sporicidal with longer exposure times.

True

True or false: Heavy metals inactivate proteins of microbes.

True

True or false: Hypochlorites are probably the most extensively used of all chlorine compounds; however, chloramines are being employed more frequently as alternatives in treating water supplies due to concerns regarding the formation of cancer-causing substances.

True

True or false: Iodine compounds can be sporicidal if used properly.

True

True or false: Quats are rated for only low-level disinfection in the clinical setting.

True

True or false: Radiation is energy emitted from atomic activities and dispersed at high velocity through matter or space.

True

True or false: Silver and mercury are still used in germicidal preparations.

True

True or false: The halogens are a group of nonmetallic elements with antimicrobial applications, including bromine, iodine, chlorine and fluorine.

True

True or false: The lowest 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 primary targets of microbial control are microorganisms that cause infection or spoilage.

True

True or false: The two primary iodine preparations are free iodine and iodophors.

True

True or false: Weak tinctures of heavy metals may be used as antiseptics on intact skin.

True

A sterile object is free of ______.

all viable microorganisms and viruses

Antimicrobial solutions with water as the solvent are called BLANK solutions.

aqueous

Antimicrobial solutions with water as the solvent are called BLANK solutions, whereas antimicrobial solutions with alcohol or water-alcohol mixtures as the solvent are called BLANK

aqueous, tinctures

A BLANK agent will inhibit the growth of bacteria, whereas a BLANK agent will kill bacteria.

bacteristatic and bactericidal

Sodium hypochlorite is also known as

bleach

BLANK spectrum action is a desirable characteristic of a germicide.

broad

Antiseptics are ______ agents applied to the skin to inhibit vegetative bacterial cells. physical chemical chemical and physical

chemical

An ethylene oxide (ETO) sterilizer is called a(n) _____.

chemiclave

Ethylene oxide, propylene oxide and BLANK dioxide are commonly used as gaseous sterilants or disinfectants.

chlorine

Gaseous and liquid BLANK compounds are mostly used for large-scale water disinfection.

chlorine

BLANK involves the permanent termination of a particular organism's vital processes, and special qualifications are often needed to define and delineate this phenomenon in microbes.

death

The lowest temperature that achieves sterilization in a given quantity of broth culture upon a 10-minute exposure is referred to as the thermal BLANK BLANK

death point

The shortest length of time required to kill all test microbes at a specified temperature is referred to as the thermal BLANK BLANK

death time

______ is the physical removal of surface oils, debris, and soil from skin to reduce the microbial load.

degermation

Boiling water can be an effective means of ______ in the clinic and home. (select all that apply) disinfection sterilization antisepsis sanitization degermation

disinfection sanitization

BLANK heat requires longer exposure times and higher temperatures than BLANK

dry, moist

BLANK heat requires longer exposure times and higher temperatures than BLANK heat.

dry, moist

Alcohols are not effective against naked viruses and bacterial BLANK

endospores

Chlorine compounds usually kill microbes by denaturing BLANK

enzymes

Iodine compounds typically kill microbes by denaturing BLANK

enzymes

To adequately sterilize using heat, temperature and length of BLANK must be considered.

exposure

True or false: Heavy metals are microbistatic.

false

As the most extensively used chlorine compounds, hypochlorites are used for: food equipment sanitation wound treatment and skin cleansing swimming pool treatments sewage and waste water disinfection household cleaning

food equipment sanitation wound treatment and skin cleansing swimming pool treatments household cleaning

Formalin is an aqueous solution of BLANK gas that is used as a potent chemical fixative and microbicide.

formaldehyde

An agent that kills fungal spores, hyphae and yeasts is called a BLANK

fungicide

The two aldehydes used most often in microbial control are BLANK and BLANK

glutaraldehyde and formaldehyde

The BLANK are a group of nonmetallic elements with antimicrobial applications, including bromine, iodine, chlorine and fluorine.

halogens

The property of having antimicrobial effects in exceedingly small amounts belongs to which class of chemicals? phenolics halogens surfactants heavy metals

heavy medals

Disinfectants are normally used only on inanimate objects because they can be toxic or harmful to BLANK and other BLANK tissues.

human, animal

Plasmolysis of bacteria in foods occurs when high concentrations of salt or sugar are added to the foods creating a BLANK environment

hypertonic

The use of sugar or salt to preserve food creates a BLANK environment for the bacteria in the foods.

hypertonic

A BLANK is a combination of iodine and an organic carrier (such as alcohol) that serves as a moderate-level disinfectant and antiseptic.

iodophor

The two primary iodine preparations are free iodine and BLANK

iodophors

Sterilization of the skin: -is hard to do but not dangerous -is highly dangerous and impractical -is easily done

is highly dangerous and impractical

Ethyl and BLANK alcohols are effective in microbial control.

isopropyl

Bactericides ______ bacteria.

kill

Gaseous and liquid chlorine compounds are mostly used for: large-scale water disinfection wound treatment and skin cleansing food equipment sanitation household cleaning

large-scale water disinfection

Quaternary ammonium compounds are considered to be BLANK -level disinfectants.

low

Cationic detergents disrupt the cell BLANK leading to a loss of selective permeability.

membrane

An agent's effect on cells is known as its BLANK of action.

mode

The property of having antimicrobial effects in exceedingly small amounts is called a(n) _____ action.

oligodynamic

BLANK methods for controlling microorganisms include heat, pressure, and radiation.

physical

The two broad categories that describe methods for controlling microbes are:

physical chemical

BLANK is energy emitted from atomic activities and dispersed at high velocity through matter or space.

radiation

The main effect of cold treatment is to:

slow the activity of microbes

Which of the following type of materials can be more reliably disinfected with a germicide? Smooth objects Porous objects

smooth objects

Household bleach is known by its chemical name BLANK

sodium hypochlorite

BLANK objects are more reliably disinfected with a germicide.

solid, smooth

An object is BLANK if it is free of all viable microorganisms including viruses.

sterile

A process that completely removes or destroys all viable microorganisms, including viruses, from an object or habitat is referred to as BLANK

sterilization

Because of concerns about botulism, commercial food canneries must _____ food items.

sterilize

Medical devices that become heavily contaminated with human tissues and fluids, must be carefully BLANK using low-temperature cabinets that employ oxidizing agents such as hydrogen peroxide and paracetic acid.

sterilized

Disinfectants are normally only used on inanimate objects because: -they are not strong enough for tissues -living tissues usually don't harbor pathogens -the high concentrations needed are harmful to living tissues

the high concentrations needed are harmful to living tissues

One of the most widely used phenolics, banned from consumer products in 2017 over concerns of development of resistance, is BLANK

triclosan