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