chp 11

Which are examples of using dry heat to sterilize or disinfect materials?

Incineration Sterilization Dry oven Sterilization

Least resistance

Most bacterial vegetative cells Fungal spores and hyphae Yeasts Enveloped viruses Protozoan trophozoites

Highest resistance

Prions, bacterial endospores (Bacillus, Clostridium)

modeate resistance

Protozoan cysts; naked viruses Bacteria with no endospores but resistant walls: Mycobacterium, Pseudomonas, Acinetobacter, other gram(-) Staphylococcus (most heat- and chemical-resistant bacteria)

Which are goals of pasteurization?

Retention of liquid qualities Reduction of microbial load

Boiling water can be an effective means of obtaining which of the following in the clinic and home?

Sanitization Disinfection

Antimicrobial chemicals can exist in what physical states?

Solid Liquid Gas

Which are examples of using moist heat to sterilize or disinfect materials?

Steam under pressure Sterilization Boiling water, hot water, pasteurization Disinfection autoclaving

All of the following describe the typical microbial population targeted by antimicrobial drugs except which of the following?

Uniform populations of like microbes

Which of the following describes dry heat?

Very high temperatures Low moisture

--- is a sterilization chamber that allows the use of steam under pressure to sterilize materials. Sterilization is achieved using an autoclave for which of the following reasons?

autoclave Pressure in the chamber increases the temperature of the steam.

Which of the following devices would not be used for dry heat conditions?

autoclave dry heat- ncineration Sterilization Dry oven Sterilization

Which of the following is a recommended method for disinfecting unsafe drinking water? Sterile milk is typically generated by which of the following?

boiling high heat

Phenolics typically kill microbes by disrupting the cell

cell wall or cell membrane

Which root indicates the ability to kill microorganisms? The root - is used to indicate the inhibition of microbial growth. What type of agent specifically destroys bacterial endospores?

cide static sporicide

The destruction, removal, or reduction in number of undesirable microbes --- is the general term used for the reduction of the microbial load in order to lower the possibility of infection or spoilage.

decontamination- microbial control

True or false: Most vegetative forms of microorganisms are susceptible to the same exposure to heat.

f- they ary

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

false- for skin and wounds

most lethal radiation radiation is most lethal from 240nm to 280nm.

gamma -Which of the following is most penetrating? uv

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

halogens

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

incineration

The bombarding of a substance by waves or particles for diagnosis, therapy, disinfection, or sterilization is referred to as

irradiation

Which of the following are examples of physical agents or mechanical means used to control microbes?

mechanical- filtration, chemical agents, liquids

When microbes are treated with temperatures that exceed their maximum growth temperature, the condition is described as which of the following?

microbicidal

higher temps are usually - lower temps-

microbicidal microbistatic

heat operates at lower temperatures for shorter times than heat which requires higher temps and longer exposure times for the same effectiveness.

moist dry

The heat treatment of perishable liquids to destroy heat-sensitive vegetative cells and prevent infection and spoilage is called Regular --- does not sterilize milk and other beverages.

pasteurization

most sterilzation is peformed using a --- Sterilization methods are usually reserved for which of the following?

physcial agent ex. heat, Dry Incineration Sterilization Dry oven Sterilization Inanimate objects

---- used for microbial control includes electromagnetic waves with shorter wavelengths.

radiation

A germicide usually cannot kill which of the following cells?

resistant can kill bactericide, fungicide, virucide, sporicidal) kill non-endospore forming pathogenic microorganisms.

In a solution, solutes are dissolved in a liquid known as the

solvent

The lowest temperature that achieves that achieves sterilization in a given quantity of broth upon a 10-minute exposure is referred to as the thermal shortest length of time required to kill all test microbes at a specified temperature

thermal death point thermal death time

microbes are not killed by regular pasteurization methods.

thermoduric

chemical lights dont kill

uv light

is non-ionizing radiation that readily induces mutations.

uv radiation

With the exception of endospores, almost all microorganisms are killed by chlorine in how many minutes?

30 min

The temperatures used in incineration must usually be above which of the following?

800 c

Which of the following is the antiseptic cleanser of choice to control MRSA and Acinetobacter outbreaks in hospitals?

Chlorhexidine

Dry heat works in which of the following ways?

Dehydrating the cell Alters protein structure Oxidizing the cell to ashes

Moist heat works mostly by which of the following ways?

Denaturing proteins

Identify any chemical agent used to control microbes.

Detergents Halogens Heavy metals