Chapter 9 Physical and Chemical control of microbes
True or False: Routine antisepsis often is completed using phenolics.
False. Phenolics may be very irritating to the skin.
________ is the destruction of microbes by subjecting them to extremes of dry heat, reducing them to ashes and gas.
Incineration
__________ are complexes of iodine and alcohol.
Iodophons
What is a chemical agent's mode of action?
Its effect on cells
Prions are _
Resistant to heat and chemicals
________ is define as growth of microorganisms in the blood or other tissues.
Sepsis
What is desiccation?
The dehydration of microbes for preservation
What is incineration?
The use of dry heat to destroy all microbes.
What does degerming apply to?
This only applies to the skin.
True or false: Tinctures and ointments are two types of heavy metal germicides.
True. There are also aqueous solutions of heavy metal germicides.
What is nonionizing radiation?
UV light
_______ radiation is most lethal from 240 nm to 280 nm.
Ultraviolet
What are examples of sanitization?
Washing utensils doing laundry scouring a countertop with soap
UV radiation is effective at disinfecting which types of materials?
air solid surfaces liquids
Degermation and _______ can be accomplished with the same procedure.
antisepsis
Iodine compounds are commonly used for
antisepsis of skin treatment of skin wounds disinfection of medical equipment
Chlorhexidine solutions are commonly used for
antisepsis of the skin
Which term identifies a chemical agent applied directly to exposed body surfaces (skin and mucous membranes), wounds, and surgical incisions to destroy or inhibit pathogens?
antiseptic
Alcohols are commonly used for
antiseptic perparation for skin degermation of skin
Antimicrobial solutions with water as the solvent are called ________ solutions, wheras antimicrobial solutions or water-alcohol mixtures as the solvent are called ________.
aqeous ; tinctures
Heavy metal germicides come in which form?
aqueous solutions ointments
A(n) _______is a sterilization chamber that allows the use of steam under pressure to sterilize materials.
autoclave
What microbial is the most resistant to physical and chemial control methods?
bacterial ENDOspores.
What type of agent will kill bacteria?
bactericidal , where cidal means to have the potential to kill
Any process or agent that inhibits bacterial growth is referred to as _______.
bacteristatic
Phenol is now limited in its use to
cesspools animal quarters drains
Ethylene oxide and _______ dioxide are commonly used as gaseous sterilants or disinfectants.
chlorine
Gaseous and liquid ________ compounds are mostly used for large-scale water disinfection.
chlorine
the effect of a germicide is affected by which of the following factors?
contamination with organic matter concentration of germicide material being treated nature of microbial population chemical action of germicdie time of exposure to germicide
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
The shortest length of time required to kill all test microbes at a specified temperature is referred to as the thermal ________ _________.
death time
Filtration has been used for what?
decontamination of air decontamination of milk products sterilization of medical products water purification
Chlorine compounds typically kill microbes by
denaturing metabolic enzymes
Phenolics typically kill microbes by:
denaturing metabolic enzymes disrupting the cell wall disrupting the cell membrane
A sterilant is a chemical that
destroys all life forms, including endospores
The goal of regular pasteurization methods is the ________ of the liquid.
disinfection
UV radiation is usually used for
disinfection
Boiling water can be an effective means of:
disinfection sanitization
Glutaraldehyde typically kills microbes by
disrupting enzyme function altering amino acids
High-level germicides can kill _______, whereas intermediate-level germicides can kill fungal spores and resistant pathogens but not endospores.
endospores
Viruses, prions, and _______ are relatively resistant to heat.
endospores
What microbial forms are relatively resistant to heat?
endospores viruses
The two microbial agents that are least resistant to physical and chemical control methods include:
enveloped viruses fungi
Which chemical is valuable for sterilization of heat-sensitive objects such as plastics, surgical and diagnostic appliances, and spices, but is more toxic than other available related gases?
ethylene oxide
To adequately sterilize using heat, temperature, and length of ________ must be considered.
exposure
Microbes can be effectively removes from air by ___________.
filtration
The straining of a fluid or air through a membrane to trap microorganisms is known as ________.
filtration.
The ______ method of pasteurization exposes liquids to higher temps for a very short time, whereas the ____ method uses ower temps for a longer period.
flash, batch
_________ are chemical agents that kill non-endospore forming pathogens.
germicides
The dosage of radiation is measured in _____.
grays
What is the most common physical agent used to control microbes?
heat
Dry hear occurs in the forms of
hot air oven an open flame
Disinfectants can be toxic or harmful to _______ tissues.
human
The use of sugar or salt to preerserve food creates a _______ environment for the bacteria in the foods.
hypertonic
What are examples of degermation?
immersing skin in chemicals surgical handscrub
Which of the following is the practical definition of microbial death?
inability to reproduce
Heavy metals typically kill microbes by
inactivating proteins
____________ of loops and needles in the lab is an example of using dry heat to sterilize materials.
incineration
The two primary iodine preparations are free iodine and ______
iodophons
A ________ is a combination of iodine and an organic carrier (such as alcohol) that serves as a moderate-level disinfectant and antiseptic.
iodophor
Ethyl and ______ alcohols are effective in microbial control.
isopropyl
Filtration is used to prepare _______ that cannot be heated, and to remove ________ contaminants that are a common source of infection and spoilage.
liquids ; airborne
Quats are rated as _______ disinfectants in the clinical setting.
low-level.
What method preserves microorganisms (and other substances) by freezing and then drying them directly from the frozen state?
lyophilization
The cell __ is responsible for preventing the loss of important molecules and stopping the entry of damaging substances.
membrane
An agent's effect on cells is known as its _______ of action.
mode
Alcohols are effective against
most bacteria enveloped viruses fungi NOT ENDOSPORES BECAUSE THEY'RE RESISTANT TO MOST CHEMICAL AGENTS!
dry oven sterilization is not useful for plastics, cotton, and ______.
paper
Items are classified as critical, semicritical, or noncritical based on _____
parts of the body contacted by the item
What are not suited for sterilization in an autoclave?
powders oils liquids
Phenolics
prevent the growth of microbes
Although they do have some drawbacks, heavy metals are used for
prevention of infection controlling microbial growth on objects preservatives skin cleansing
Glutaraldehyde affects which type of macromolecule?
proteins
________ is energy emitted from atomic activities and dispersed at high velocity through matter or space.
radiation
Substances like oils or waxes are not effectively sterilized in an autoclave because they
repel moisture
Which cellular structure is involved in translation?
ribosome
What are desirable qualities in a germicide?
selective toxicity penetrating ability rapid action solubility in a solvent broad-spectrum action
_____ and mercury are heavy metals that are still used in germicidal preparations.
silver
Soaps and quats are commonly used for
skin cleansing sanitization of food preparation equipment sanitzation of the home disinfection of facilities
The main effect of cold treatment is to _______ the activity of microbes.
slow
Which compounds are typical examples of sanitizers?
soap detergent
A _______ is an agent that can destroy bacterial endospores.
sporicide
The root ______ is used to indicate the inhibition of microbial growth.
static
A sporicide agent can also be a _____ because it can destroy bacterial endospores and leave an object free of all life.
sterilant
An object is ________ if it is free of all viable microorganisms including viruses
sterile
A process that compleely removes or destroys all viable microorganisms, including viruses, from an object or habitat is referred to as __________ .
sterilization
A _____ is an agent that disrupts the lipid bilayer of membranes and alters the membrane's permeability.
surfactant
Identify examples of antisepsis
swabbing skin with albogol before a venipicture washing hands with a germ soap
The four general cellular targets of antimicrobial agents are:
the cell wall nucleic acid synthesis protein function the cell membrane
True of false: heavy metals may be used for topical germicides and ointments.
true.
All of the following describe the typical microbial population targets by antimicrobial drugs except:
uniform populations of like microbes
What is a concern when attempting to control a microbial population?
variable resistance
Chlorohexidine can kill/inactivate most
viruses bacteria
Aldehydes are organic substances that contain a _______ functional group on a terminal carbon.
-CHO
What are tinctures?
Antimicrobial solutions with alcohol or water-alcohol mixtures as the solvent.
________ is a term referring to a procedure or process designed to prevent entry of infectious agents into sterile tissues.
Asepsis
Which is the term used for any process or agent that inhibits bacterial growth? Bactericidal or bacteriostatic?
Bacteriostatic
Ultraviolet radiation affects the _________ of cells.
DNA
_________ 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
_________ is the general term used for the reduction of the microbial load in order to lower the possibility of infection or spoilage.
Decontamination
________ is the general term used for the reduction of the microbial load in order to lower the possibility of infection or spoilage
Decontamination , example would be decontaminating utensils at the restraunt
________ is the physical removal of surface oils, debris, and soil from skin to reduce the microbial load.
Degermination
__________ is the physical removal of surface oils, debris, and soil from skin to reduce the microbial load.
Degermination, hand sanitizer
Which term identifies the disruption of proteins from their native state?
Denaturation
__________ is the dehydration of microorganisms to inhibit or preserve them.
Dessication
__________ is the use of a physical process of a chemical to destroy vegetative pathogens but not bacterial endospores, usually on inanimate surfaces.
Disinfection
Ethylene oxide typically kills microbes by:
Disrupting enzyme function Blocking DNA replication
What is the mode of action for phenolics?
Disruption of cell wall or membrane