MICRO - CH 9

An process or agent that inhibits bacterial growth is referred to as ____ A. Bacteriostatic b. Bactericidal

a

Soaps and detergents are typical examples of a. Sanitizers B. Disinfectants C. High-level germicides

a

Substances like oils or waxes are not effectively sterilized in an autoclave because they A. Repel moisture b. Are heat-liable c. Are generally not contaminated

a

UV radiation is usually used for ___ a. Disinfection b. Sterilization

a

Washing laundry, doing dishes , and wiping down counters with soap are all examples of A. Sanitization b. Antisepsis c. Disinfection D. Sterilization

a

What is the thermal death time? A. The shortest length of time required to kill all test microbes at a specified temperature b. The lowest temperature at which all microbes are killed within ten minutes c. The time it takes to reduce a microbial population to safe levels

a

Which cellular structure is involved in translation? A. Ribosome B. Cell wall c. Smooth ER D. Nucleus E. Cell membrane

a

Which level of chemical decontamination by a germicide can result in sterilization? A. High level b. Low level C. Intermediate level

a

Which type of detergents are more effective? A. Cationic b. Anionic

a

____ is a term referring to a procedure or process designed to prevent entry of infectious agents into sterile tissues A. Asepsis B. Sepsis

a

Determination and ______ can be accomplished with the same procedure

antisepsis

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

antisepsis

A chemical agent applied directly to exposed body surfaces (skin and mucous membranes), wounds and surgical incisions to destroy to inhibit pathogens is an

antiseptic

Antimicrobial solutions with water as the solvent are called ______ solutions

aqueous

a sterilization chamber that allows the use of steam under pressure to sterilize materials

autoclave

Boiling water can be effective means of A. Antisepsis b. Disinfection C. Sterilization

b

Chlorhexidine solutions are commonly used for a. Disinfection of food preparation equipment b. antisepsis of skin c. Disinfection of medical equipment D. Household cleaning E. Disinfection of drinking water

b

Iodine compounds are commonly used in the ____ setting a. Household b. Clinical

b

What is a chemical agent's mode of action? a. Its level of killing power b. Its effect on cells C. The list of species that it affects

b

What is a concern when attempting to control a microbial population ? A. Microbial antagonism b. Variable resistance c. Uniformity of the population

b

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

b

Which type of agent will kill bacteria? A. Bacteristatic B. Bactericidal

b

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

bacteristatic; bactericide

A liquid can be suctioned through precise uniform pores for sterilization by A. Desiccation B. Irradiation C. Filtration

c

A sporicide agent can also be a _____ because it can destroy bacterial endospores and leave an object free of life A. Disinfectant b. Antiseptic c. Sterilant

c

An object can be: a. Sterile, mostly sterile or not sterile b. Several degrees of sterility C. Either sterile or not sterile

c

Disinfection destroys A. All types of microorganisms b. Bacterial cells and endospores C. Only vegetative bacterial cells D. Only viruses

c

In sterilization ____ are destroyed or removed A. Bacteria and viruses but not endospores b. Only bacteria c. All microorganisms

c

Liquids can be sterilized by suctioning through a filter with uniform pores. Viruses can be eliminated from the liquid by A. Increasing the suction pressure b. Boiling after filtration C. Using a small pore size

c

Prions are A. Sensitive to heat but resistant to chemicals b. Resistant to heat but sensitive to chemicals c. Resistant to heat and chemicals D. Sensitive to heat and chemicals

c

Sepsis is defined as A. Death of tissue due to microbial growth b. Growth of microorganisms in the water supply c. Growth of microorganisms in the blood or other tissues

c

Surgical hands scrubbing os an example of A. Disinfection b. Sterilization c. Degermation

c

Ultraviolet radiation is most lethal from _____ a. 100-400nm b. 300-600nm c. 240-280nm d. 1-25nm

c

_____ are chemical agents that kill non-endospore forming pathogens. a. Insecticides b. Germistatins C. Germicides

c

Chemical agents that can destroy all forms of life, including endospores are called ____ A. Germicides b. Detergents C. Antiseptics D. Sterilants

d

Chlorine compounds typically kill microbes by A. Disrupting the cell membrane b. Inhibiting protein synthesis c. Inhibiting RNA synthesis D. Denaturing metabolic enzymes E. Causing mutations in DNA

d

To prepare a common disinfectant like lysol by performing a 1:200 dilution, you would mix A.one part water to 200 parts lysol b.[There is insufficient information to calculate the dilution.] C. One part lysol to 200 parts ethanol D. One part lysol to 200 parts water

d

Ultraviolet radiation affects the ____ of cells. A. Membrane fluidity b. Permeability c. Proteins d. DNA

d

What is desiccation? a. The boiling of microbes for preservation b. The steaming of microbes for preservation c. The freezing of microbes for preservation D. The dehydration of microbes for preservation

d

What is filtration? a. The use of a chemical sterilant to kill all microbial life b. The use of intermittent heat and pressure to destroy microbes c. The use of radiation to eliminate most microbial life D. The straining of a fluid or air through a membrane to trap microorganism's

d

When decontaminating a metal instrument that has blood on it, you should A. Treat with a chemical disinfectant, then remove any blood that Is visible b. Discard it, as it cannot be decontaminated c. Immerse the object in an appropriate chemical disinfectant d. First remove the blood, then treat with a chemical disinfectant

d

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 mechanical removal of most microbes from an animate or inanimate surface

decontamination

The disruption of proteins from their native state is known as _____

denaturation

Which of the following is the most common physical agent used to control microbes A. Dessication B. Filtration c. Cold d. Germicide E. Heat

e

Viruses, prions, and ______ are relatively resistant to heat

endospores

The effect of a germicide is affected by the time of ____

exposure

kills fungal spires, hyphae and yeast

fungicide

Disinfectants can be toxic or harmful to______ tissue.

human

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

hypertonic

A virucide _____ viruses

inactivates

the destruction of microbes by subjecting them to extremes of dry heat, reducing them to ashes and gas

incineration

Cationic detergents disrupt the cell ______

membrane

the cell ______is responsible for preventing the loss of important molecules and stopping the entry of damaging substances

membrane

Prions are resistant to inactivation by heat, _______, and chemicals

radiation

the energy emitted from atomic activities and dispersed at high velocity through matter or space

radiation

The inability to _______ is the practical definition of microbial death

reproduce

The main effect of cold treatment is to ______ the activity of microbes

slow

______ objects are more reliably disinfected with a germicide

smooth

can destroy bacterial endospores

sporicide

inhibition of microbial growth

stat-, -stasis

An object is _______ 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

sterilization

To adequately sterilize using heat, temperature and length of_____ must be considered

time

-cide

to kill

True or false: death involves the permanent termination of a particular organism's vital process

true

True or false: soaps and detergents are sufficient on their own for home cleaning, and additional antimicrobial agents are likely to lead to resistance in the microbes.

true

True or false: the primary targets of microbial control are microorganisms that cause infection or spoilage

true

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

Aldehydes

_______ spectrum action is a desirable characteristic of a germicide.

Broad

a combination of iodine and an organic carrier (such as alcohol ) that serves as a moderate disinfectant and antiseptic

Iodophor

is a method for preserving microorganisms by freezing and then drying them directly from the frozen state

Lyophilization