Chapter 11 review
Dyes are important for which of the following reasons?
*Chemotherapeutic drugs *Staining techniques *Selective and differential media
Hydrogen peroxide is commonly used to disinfect which of the following?
*Surgical implants *Bedding
Which root(s) indicates the ability to prevent microbial growth?
-stasis, -static
The kilogray is equal to ______ write the number in grays.
1000
At sea level, water boils at which temperature?
100C
All non-heat resistant forms of bacteria, yeasts, molds, protozoa, worms and viruses are destroyed by exposure to 80οC for which minimum amount of time?
20 minutes
With the exception of endospores, almost all microorganisms are killed by chlorine in how many minutes?
30
The temperature used in incineration must usually be above which of the following?
800C
OPA typically kills microbes by which mechanisms?
Altering amino acids Disrupting enzyme function
Glutraldehyde typically kills microbes by which method?
Altering amino acids Disrupting enzyme functions
Formaldehyde typically kills microbes by which method?
Altering proteins Attachment to nucleic acids
Dry heat works in which of the following ways?
Alters protein structure, oxidizing the cell to ashes, dehydrating the cell
Cationic detergents are more effective than _______ detergents.
Anionic
A(n) ______ is a sterilization chamber that allows the use of steam under pressure to sterilize materials.
Autoclave
Which of the following devices would not be used for dry heat conditions?
Autoclave
ETO is a strong alkylating agent that does which of the following?
Blocks enzymatic reactions Blocks DNA synthesis
____ species, which can cause undulant fever, are destroyed by pasteurization.
Brucella
Which of the following are the main drawbacks to heavy metals?
Cause allergic reactions Microbial resistance Can be toxic if inhaled
How do surfactants work to destroy microorganisms?
Cause leaky membranes
Identify the 4 general cellular targets of anti microbial agents
Cell walls, cell membranes, protein and nucleic acid synthesis, and protein structure and function
Which of the following is the antiseptic cleanser of choice to control MRSA and Acinetobacter outbreaks in hospitals?
Chlorhexidine
One of the greatest concerns in the canning industry is to prevent the growth of which of the following bacteria?
Clostridium botulinum
The phenol ______ quantitively compares the effectiveness of a chemical to that of phenol.
Coefficient
Which of the following are disadvantages using ETO?
Damages mucous membranes if in direct contact Explosiveness Rated as a carcinogen by the government
The lowest temperature that achieves sterilization in a given quantity of broth upon a 10-minute exposure is referred to as the thermal ________ _______.
Death point
Which of the following is the use of physical or chemical agents to destroy or remove most microbes from animate or inanimate surfaces?
Decontamination
Moist heat works by which of the following ways?
Denaturing proteins
Uv light can cause pyrimidine _____ to form in the genomes of microbes.
Dimers
Usually, UV rays are used for which of the following?
Disinfection
Which of the following includes removal/inactivation of harmful products of microbes like toxins?
Disinfection
Bailing water can be an effective means of obtaining which of the following in the clinic and home?
Disinfection Sanitization
Phenolics typically kill microbes by which of the following methods?
Disrupting the cell wall Disrupting the cell membrane Denaturing metabolic enzymes
Which are not effects of chlorine dioxide on microbes?
Disruption of cell wall Mutation of DNA Change in membrane permeability
What is the effect of chlorine dioxide on microbes?
Disruption of proteins
As the volume of a solution to be autoclaved increases, what must also happen?
Duration increase
___ and ___ oxide are used mainly as disinfectant-sterilants for some foods and plastic items.
ETO and propylene
Which organisms typically cannot be destroyed by Cationic detergents?
Endospores Resistant viruses
The microbial agents that are least resistant to physical and chemical control methods include which of the following??
Enveloped viruses Bacterial vegetative cells
_______ oxide is valuable for sterilization of heat-sensitive objects such as plastics, surgical and diagnostic appliances, and spices, but other related gasses are available that are less toxic.
Ethylene
True or False: Halogens are only microbistatic
False
True or False: most vegetative forms of microorganisms are susceptible to the same exposure to heat.
False
True or false: all viruses have the same susceptibility to heat.
False
True or false: incineration is an example of using moist heat to sterilize or disenfect materials.
False
True or false: at cold temperatures, all microorganisms are inhibited and can no longer secrete their toxins.
False: Some psychrotrophs will continue to grow and secrete their toxic products.
The straining of a fluid or air through a membrane to trap microorganism's is known as ________.
Filtration
____________ is a 37% solution of formaldehyde gas dissolved in water.
Formalin
Contaminants that can have far-reaching effects if not adequately controlled include which of the following?
Fungal hyphae and spores Bacterial vegetative cells
What types of microbes are killed by intermediate-level germicides?
Fungal spores, Resistant pathogens, Viruses
Which of the following devices emits ionizing rays?
Gamma ray machines, Cathode ray machines, X-ray machines
_____, an aldehyde, is one of the few chemicals that is officially accepted as a sterilant and a high-level disinfectant
Glutaraldehyde
________, an aldehyde, is one of the few chemicals that is officially accepted as sterilant and a high-level disinfectant.
Glutaraldehyde
Which of the following are the two aldehydes used most often in microbial control?
Glutaraldehyde and ortho-phthaldehyde
Identify any chemical agent used to control microbes.
Halogens, Detergents, Heavy metals
Which is the most prominent among anti microbial physical agents?
Heat
Which of the following viruses is the most resistant to heat?
Hepatitis A
What is the main disadvantage of using formalin?
Hurts people in the same way it kills microbes
Which of the following are uses for BPL?
Inactivate viruses in vaccines Disinfect whole rooms Sterilize bone grafts
What are the effects of adding pressure to water in an autoclave?
Increases boiling point of water Increases temperature of steam
Which of the following is the principle benefit of cold treatment?
Inhibition of microbial activity
Which of the following materials require high-level germicides?
Invasive medical devices
Which is an advantage of glutaraldehyde?
It has a low level of toxicity It can be used on plastics It's reliably sporicidal
Which is the definition of sepsis?
It is growth of microorganisms in the blood or other tissues.
Which is not an advantage of glutaraldehyde?
It is highly stable in the environment.
why is ethylene oxide considered an acceptable chemical sterilant?
It is reliably sporicidal.
Which of the following describes dry heat?
Low moisture Very high temperatures
The process of degermation usually involves which of the following?
Mechanical scrubbing Immersion in chemicals
What materials require intermediate germicides?
Medical devices in contact with membranes
Surfactants typically cause damage to cell
Membranes
Silver and __ are still used in germicidal preparations.
Mercury
The Liquid Metal, ________, can be very toxic to humans if it is ingested, inhaled or absorbed through the skin, even small doses.
Mercury
Hydrogen peroxide can decompose in the presence of which of the following?
Metals, Light, Catalase
Pasteurization of milk destroys ______ tuberculosis.
Mycobacterium, M., or M
Which is the principle macromolecule in cells affected by UV radiation?
Nucleic acids
Alcohols are colorless hydrocarbons with one or more _______ functional groups.
OH
Alcohols are colorless hydrocarbons with one or more _______ functional groups.
OH-
Which of the following describes ortho-phthalatehyde?
Pale blue liquid
Regular ___ does not sterilize milk and other beverages.
Pasteurization
The heat treatment of perishable liquids to destroy heat-sensitive vegetative cells and prevent infection and spoilage is called _________.
Pasteurization
Although they do have some drawbacks, heavy metals are used for which of the following?
Preservatives Prevention of infection Controlling microbial growth on objects
Identify the beneficial effects of irradiated food
Reduction of bacterial pathogens Longer shelf life
Which explains why food items in the refrigerator eventually spoil?
Refrigerator temperature only slows the activity of most microbes.
Which are goals of pasteurization?
Retention of liquid qualities Reduction of microbial load
A strong _______ solution is one of the substances that reliably destroys prions.
Sodium
Which of the following vegetative bacterial cells is more resistant to moist heat?
Staphylococcus aureus
A chemical agent that can destroy bacterial endospores and have an inanimate object free of all life is known as which of the following?
Sterilant
Why aren't bromine and Florine routinely used in germicidal preparations?
They are dangerous
Which are disadvantages to the use of quats?
They are unreliable against resistant bacteria. Their effectiveness is lowered by the presence of organics.
Which are not disadvantages of using quats?
They are usually irritating to the skin. They are unstable at room conditions.
What is the disadvantage of phenolics?
They can be irritating to the skin and mucous membranes.
What property of phenolics contributes to their usefulness?
They continue to work in the presence of organic matter.
True or False: Catheters, endoscopes, and implants are not heat-sterlizeable.
True
True or false: microbistatic antiseptics and drugs are used to control microorganisms in the body because microbicidal compounds can be toxic to the human body.
True
______ radiation is most lethal from 240nm to 280nm.
UV
_______ radiation is non-ionizing radiation that readily induces mutations.
UV
Chemical agents used to control microbes include all of the following except which one?
UV light
Which environmental conditions make chlorine unstable?
UV light Alkaline pH
All of the following describe the typical microbial population targeted by anti microbial drugs EXCEPT which of the following?
Uniform populations of like microbes
Which form of light has low penetration value so, therefore, is considered useful as a disenfectant and not a sterilizer?
Uv
Which organisms can be destroyed by catatonic detergents?
Vegetative bacteria
Which of the following are the least resistant to moist and dry heat?
Vegetative states of bacteria Vegetative states of fungi
Phenol is typically kill microbes disrupting the cell ______ or _______.
Wall, membrane
___ or alkalis are limited in their application by their corrosive and hazardous nature.
acids
_______ are organic substances that contain a -CHO functional group on a terminal carbon.
aldehydes
A sterile object is free of which of the following?
all viable microorganisms and viruses
Which base is a major component of detergents and cleansers?
ammonium hydroxide
Antimicrobial solutions with water as the solvent are called ________ solutions, whereas antimicrobial solutions with alcohol or water-alcohol solutions are called _______.
aqueous; tinctures
________ is a term referring to a condition of free pathogenic microorganisms or a procedure or process designed to prevent entry of infectious agents.
asepsis
Which are examples of using moist heat to sterilize or disinfect materials?
autoclaving, boiling, pasteurization
Which is typically the most resistant to heat?
bacterial endospores
Which microbial agent is the most resistant to physical and chemical control methods?
bacterial endospores
Which typically describes cold temperatures?
bacteriostatic
BPL is the acronym for
betapropiolactone
Which of the following is a recommended method for disinfecting unsafe drinking water?
boiling
______ water can be an effective means of disinfection in the home.
boiling
_______ spectrum action is a desirable characteristic of a germicide.
broad
Which of the following are some of the desirable qualities in a germicide?
broad-spectrum action penetrating ability rapid action selective toxicity solubility in a solvent
Another name for phenol is ____ acid
carbolic
Most microbial cells can produce which of the following to inactivate hydrogen peroxide?
catalase
Which is the major cellular structure affected by alcohols?
cell membrane
Chlorhexidine targets the __________ _______ by lowering surface tension and causes the denaturation of __________.
cell membrane proteins
Which of the following compounds are commonly used as gaseous sterilants or disinfectants?
chlorine dioxide, ethylene oxide, propylene oxide
Which root indicates the ability to kill microorganisms?
cide
Because of our perception of temperature, irradiation is considered a what type of sterilization?
cold
Microbial control methods are referred to as ____ procedures
decontamination
Biological matter such as serum, blood or urine has which of the following effects on a germicide?
decreases effectiveness
Which of the following is a term used to describe the reduction of microbial load on living tissues through mechanical means (e.g using a scrubbing brush)?
degermation
A 75% concentration of alcohol usually affects microbes by which of the following?
denaturing proteins
Iodine compounds typically kill microbes due to which of the following?
denaturing proteins
A pyrimidine _____ is the union of two adjacent pyrimidines on the same DNA strand, brought about by exposure to UV light.
dimer
Cationic detergents typically work by which of the following methods?
disrupting the cell membrane
_____ heat works by dehydrating the cell and/or oxidizing it to ashes.
dry
What is adjusted when autoclaving large, bulky loads instead of light loads
duration
Radiation is characterized by a range of wavelengths known as the _____ _____.
electromagnetic spectrum
Heavy metals are not able to reliably sterilize materials because they do not affect ________.
endospores
Which type of microbe is not killed or inactivated by intermediate-level germicides?
endospores
Which two alcohols are effective in microbial control?
ethyl and isopropyl
ETO is the acronym for
ethylene oxide
What is the process of straining a fluid or air through a membrane to trap microorganisms?
filtration
The primary targets of microbial control are microorganisms that cause which of the following?
food spoilage and disease
Which of the following are chemical agents that kill non-endospore forming pathogens?
germicides
Which of the following are examples of physical agents or mechanical means used to control microbes?
heat, filtration, radiation
The property of having antimicrobial effects in exceedingly small amounts belongs to which class of chemicals?
heavy metals
Sterile milk is typically generated by which of the following?
high heat
Heavy metals typically kill microbes by which of the following methods?
inactivating proteins
Sterilization methods are usually reserved for which of the following?
inanimate objects
_______ is the destruction of microbes by subjecting them to extremes of dry heat, reducing them to ashes and gas.
incineration
Which type of germicide is used to treat medical devices in contact with membranes?
intermediate
The bombarding of a substance by waves or particles for diagnosis, therapy, disinfection, or sterilization is referred to as.
irradiation
_______ is the process of bombardment with radiation at the cellular level to control microbes.
irradiation
A bactericide ____ bacteria.
kills
In what unit is radiation measured?
kilograys
Identify the organic acid that is added to sauerkraut to prevent the growth of anaerobic bacteria, especially clostridia.
lactic acid
What must be considered to ensure adequate sterilization by heat?
length of exposure and temperature
Antimicrobial chemicals can exist in what physical states?
liquid, solid, gas
The size of a microbial population is often referred to as the microbial _____.
load
Cationic detergents disrupt the cell ________.
membrane
If the cell _______ is damaged by an agent, it loses its selective permeability and cannot prevent the loss or entrance of substances.
membrane
The cell __ is responsible for preventing the loss of important molecules and stopping the entry of damaging substances.
membrane
Which of the following heavy metals are still used in germicidal preparations?
mercury and silver
When microbes are treated with temperatures that exceed their maximum growth temperature, the condition is described as which of the following?
microbicidal
Regarding the use of the terms microbicidal and microbistatic, higher temperatures are usually __, whereas lower temperatures are usually __.
microbicidal; microbistatic
An agent's effect on cells is known as its __________ of ____________________.
mode of action
Many perishable substances are processed with _____ heat to allow for shelf storage time of months or years.
moist
______ heat works primarily by denaturing proteins.
moist
Anionic means _____ charged.
negatively
Which of the following reason best explains why the normal boiling point of water is insufficient to kill endospores?
not hot enough
The property of having antimicrobial effects in very small amounts is which type of reaction?
oligodynamic
Most sterilization is performed using a ______ agent, such as heat.
physical
Identify the organic acid that is commonly incorporated into breads to retard molds.
propionic acid
Heavy metals inactivate which macromolecules found in microbes?
proteins
_______ used for microbial control includes electromagnetic waves with shorter wavelengths
radiation
The inability to ______ even under optimal growth conditions is practical definition of microbial death.
reproduce
A germicide usually cannot kill which of the following cells?
resistant
Which cellular structure is involved in translation?
ribosome
Most soaps would be considered a _____ while bleach solutions are considered a _____.
sanitizer, disinfectant
Aniline dyes are used for which of the following?
skin infections
Which of the following is considered a surfactant?
soap
In dilutions a small amount of the ______ is diluted in a large volume of solvent to achieve a certain ratio.
solute
In a solution, solutes are dissolved in a liquid known as the ___________.
solvent
Ethylene oxide is well recognized as a chemical sterilant against which of the following?
spores
Metals with high molecular weights have difficulty in destroying which of the following effectively?
spores/endospores
Which of the following describe iodine compounds if they are used at proper concentrations and used for the correct period of time?
sporicidal
What type of agent specifically destroys bacterial endospores.
sporicide
The root- ______ is used to indicate the inhibition of microbial growth.
static
Chemical agents that can destroy all forms of life, including endospores, are called which of the following?
sterilants
Which of the following can be high-level germicides?
sterilants
What process completely removes or destroys all viable microorganisms, including viruses, from an object or habitat?
sterilization
What term is used to describe chemical agents that work by lowering the surface tension of cell membranes?
surfactants
Aldehydes are organic substances that contain a -CHO functional group on a _______ carbon.
terminal
Disinfectants are normally only used on inanimate objects for which reason?
the high concentrations needed are harmful to living tissues
Which of the following is the practical definition of microbial death?
the inability to reproduce
shortest length of time required to kill all test microbes at a specified temperature
thermal death time
Which microbes are resistant to the harmful effects of high temperature?
thermoduric
____ microbes are not killed by regular pasteurization methods.
thermoduric
Typically, increases to temperature can result in a reduction in ______ to ensure adequate sterilization by heat.
time
Typically, increases to temperature can result in a reduction in _______ to ensure adequate sterilization by heat.
time
Which word is typically used to describe the size of bacterial population?
to load
The synthesis of proteins involves ribosomes that are used in a process called ________.
translation
Alcohols are most effective at destroying which of the following?
vegetative bacteria and enveloped viruses
Identify the products of the decomposition of hydrogen peroxide.
water and oxygen
If a bacterial cell is placed in 100% alcohol , what happens to the water in the cell?
water leaves the cell
Radiation of pork products can reduce the number of Trichinella, which are what type of microbe?
worm
Which describes glutaraldehyde?
yellow liquid
