Ch 11: physical and chemical agents from microbial control

Dyes are important for which of the following reasons?

*Chemotherapeutic drugs *Staining techniques *Selective and differential media

OPA typically kills microbes by which mechanisms?

Altering amino acids Disrupting enzyme function

Which of the following are the main drawbacks to heavy metals?

Cause allergic reactions Microbial resistance Can be toxic if inhaled

Chlorhexidine targets the __________ by lowering surface tension and causes the denaturation of______.

Cell membrane Proteins

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

Chlorhexidine

Which of the following compounds are commonly used as gaseous sterilants or disinfectants?

Chlorine dioxide Ethylene oxide Propylene oxide

The phenol_____ quantitatively compares the effectiveness of a chemical to that of phenol.

Coefficient

Microbial control methods are referred to as_____ procedures

Decontamination

Which of the following is the use of physical or chemical agents to destroy or remove most microbes from animate or in animate surfaces?

Decontamination

____ and _____ oxide are used mainly as disinfectant-sterilants for some foods and plastic items.

ETO and propylene

_____oxide is valuable for sterilization of heat-sensitive objects such as plastics, surgical and diagnostic appliances, and spices, but other related gases are available that are less toxic

Ethylene

Acids or alkalis are limited in their application because they have limited reliability.

False

What is the process of straining a fluid or air through a membrane to trap organisms?

Filtration

Which of the following are the two aldehydes most often used in microbial control?

Glutaraldehyde and ortho-phthaldehyde

Which is the most prominent among anti-microbial life physical agents?

Heat

Which of the following is the particle definition of microbial death?

Inability to reproduce

If the cell____ is damaged by an agent, it loses its selective permeability, and cannot prevent the loss or entrance of substances

Membrane

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 in small doses.

Mercury

Hydrogen peroxide can decompose in the presence of which of the following?

Metals, Light, Catalase

Which of the following describes ortho-phthalaldehyde?

Pale blue liquid

____used for microbial control includes electromagnetic waves with shorter wavelengths.

Radiation

Which organisms typically can not be destroyed by cationic detergents?

Resistant viruses Endospores

A strong ___ hydroxide solution is one of the substances that reliably destroys prions.

Sodium

What process completely removed or destroys all viable microorganisms, including viruses, from an object or habitat?

Sterilization

Why aren't bromine and fluorine routinely used in germicidal preparations?

They are dangerous

___ radiation is non-ionizing radiation that readily induces mutations.

UV

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

Uniform populations of like microbes

____ 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

Which typically describes cold temperatures?

bacteriostatic

What is another name for phenol?

carbolic acid

Which is the major cellular structure affected by alcohols?

cell membrane

Radiation is characterized by a range of wavelengths known as the _____ _____.

electromagnetic spectrum

ETO is the acronym for _______

ethylene oxide

The primary targets of microbial control are microorganisms that cause which of the following?

food spoilage and disease

Which of the following is most penetrating?

gamma rays

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

Antimicrobial chemicals can exist in what physical states?

liquid, solid, gas

The cell ___ is responsible for preventing the loss of important molecules and stopping the entry of damaging substances.

membrane

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

The inability to ___ even under optimal growth conditions is the practical definition of microbial death.

reproduce

Most soaps would be considered a _____ while bleach solutions are considered a _____.

sanitizer, disinfectant

Soaps can be reliably used in the clinical and home setting as which of the following?

sanitizers

Aniline dyes are used for which of the following?

skin infections

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

solvent

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

Aldehydes are organic substances that contain a -CHO functional group on a ____ carbon.

terminal

___ radiation is most lethal from 240nm to 280nm

ultraviolet

Which organisms can be destroyed by cationic detergents?

vegetative bacteria

Alcohols are most effective at destroying which of the following?

vegetative bacteria and enveloped viruses

True or false: halogens are only microbistatic.

False

How are many cultures of microbes routinely preserved?

freezing

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

heat, filtration, radiation

Metals with a ______ molecular weight can be toxic in low amounts.

high

Which level germicides can function as sterilants?

high

In what unit is radiation measured?

kilograys

In dilutions, a small amount of the _____ is diluted in a large volume of solvent to achieve a certain ratio.

solute

Identify the products of the decomposition of hydrogen peroxide.

water and oxygen

Which describes glutaraldehyde?

yellow liquid