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
