CH. 11 Questions
All non-heat resistant forms of bacteria, yeasts, molds, protozoa, worms and viruses are destroyed by exposure to 80οC for which minimum amount of time?
20 minutes
With the exception of endospores, almost all microorganisms are killed by chlorine in how many minutes?
30 minutes
In sterilization, which of the following are removed or destroyed?
All microorganisms
Antimicrobial solutions with water as the solvent are called________solutions, whereas antimicrobial solutions with alcohol or water-alcohol solutions are called ________.
Aqueous, Tinctures
An ________ is a sterilization chamber that allows the use of steam under pressure to sterilize materials.
Autoclave
Which microbial agent is the most resistant to physical and chemical control methods?
Bacterial Endospores
Which is typically the most resistant to heat?
Bacterial endospores
Contaminants that can have far-reaching effects if not adequately controlled include which of the following?
Bacterial vegetative cells Fungal hyphae and spores
________spectrum action is a desirable characteristic of a germicide.
Broad
Which is the major cellular structure affected by alcohols?
Cell membrane
Which is not a form of chlorine typically used in microbial control?
Chloride
Microbes that are present at any given time and place that are undesirable or unwanted are known as which of the following?
Contaminants
Which of the following is the mechanical removal of most microbes from animate or inanimate surface?
Decontamination
________ is the general term used for the reduction of the microbial load in order to lower the possibility of infection or spoilage.
Decontamination
Most________ methods employ either _________ or chemical agents to control microorganisms.
Decontamination, physical
Biological matter such as serum, blood or urine has which of the following effects on a germicide?
Decreases effectiveness
Identify any chemical agent used to control microbes.
Detergents Heavy Metals Halogens
Usually, UV rays are used for which of the following?
Disinfection
Chemical agents that can destroy all forms of life, including _________ are called sterilants.
Endospores
Alcohols are most effective at destroying which of the following?
Enveloped viruses Vegetative Viruses
True or false: Biological matter such as serum, blood or urine increases the effectiveness of a germicide.
False
The primary targets of microbial control are microorganisms that cause which of the following?
Food spoilage, Disease
Which of the following are examples of physical agents or mechanical means used to control microbes?
Heat Filtration Radiation
Which level germicides can function as sterilants?
High Level germicides
Metals with a ________ molecular weight can be tolix in low amounts.
High/Large
Sterilization methods are usually reserved for which of the following?
Inanimate objects
Which of the following materials require high-level germicides?
Invasive medical devices
Hydrogen peroxide can decompose in the presence of which of the following?
Light Catalase Metals
Antimicrobial chemicals can exist in what physical states?
Liquid Solids Gas
Which of the following heavy metals are still used in germicidal preparations?
Mercury and Silver
The germicidal effects of hydrogen peroxide are due to the direct and indirect actions of which gas?
Oxygen
Identify the products of the decomposition of hydrogen peroxide.
Oxygen and Water
Most sterilization is performed using a _______ agent, such as heat.
Physical agent
Which are goals of pasteurization?
Retention of Liquid qualities Reduction of microbial load
Most soaps would be considered a ________ while bleach solutions are considered a __________.
Sanitizer/Cleaner, disinfectant
Hydrogen peroxide is commonly used to disinfect which of the following?
Surgical implants and bedding
Which are NOT disadvantages of using quats?
They are usually irritating to the skin They are unstable at room conditions.
Which form of light has low penetration value so, therefore, is considered useful as a disinfectant and not a sterilizer?
UV light
Which environmental conditions make chlorine unstable?
UV light Alkaline pH
All of the following describe the typical microbial population targeted by antimicrobial drugs except which of the following?
Uniform populations of like microbes
The heat treatment of perishable liquids to destroy heat-sensitive vegetative cells and prevent infection and spoilage is called ______?
pasteurization