Question 1

Each of the following is a target of antimicrobial agents except ______.

Accepted Answer

A) cell walls 
B) cell membranes 
C) ribosomes 
D) cellular proteins 
E) cytoplasm 
A) cell walls 
B) cell membranes 
C) ribosomes 
D) cellular proteins 
E) cytoplasm

Question 2

Which is correct regarding the rate of microbial death?

Accepted Answer

A) Cells die at increasingly greater rates. 
B) Only older cells die in a culture. 
C) Cells in a culture die at a constant rate. 
D) Upon contact with the control agent, all cells die at one time. 
E) Cells become metabolically inactive but are never killed. 
A) Cells die at increasingly greater rates. 
B) Only older cells die in a culture. 
C) Cells in a culture die at a constant rate. 
D) Upon contact with the control agent, all cells die at one time. 
E) Cells become metabolically inactive but are never killed.

Question 3

Which of the following is not a primary target of milk pasteurization?

Accepted Answer

A) Salmonella 
B) Campylobacter jejuni 
C) Lactobacillus 
D) Listeria monocytogenes 
E) Brucella 
A) Salmonella 
B) Campylobacter jejuni 
C) Lactobacillus 
D) Listeria monocytogenes 
E) Brucella

Question 4

Endospores can be inactivated by

Accepted Answer

A) dry heat at 170°C for 2 hours. 
B) incineration. 
C) glutaraldehyde for 3 or more hours. 
D) ethylene oxide for 3 or more hours. 
E) All of the choices are correct. 
A) dry heat at 170°C for 2 hours. 
B) incineration. 
C) glutaraldehyde for 3 or more hours. 
D) ethylene oxide for 3 or more hours. 
E) All of the choices are correct.

Question 5

All of the following are alkylating control agents except ______.

Accepted Answer

A) iodophor 
B) propylene oxide 
C) formaldehyde 
D) ethylene oxide 
E) glutaraldehyde 
A) iodophor 
B) propylene oxide 
C) formaldehyde 
D) ethylene oxide 
E) glutaraldehyde

Question 6

What instrument is most effective for pressure-temperature sterilization?

Accepted Answer

A) Water-bath 
B) Autoclave 
C) Incubator 
D) Oven 
E) Bunsen burner 
A) Water-bath 
B) Autoclave 
C) Incubator 
D) Oven 
E) Bunsen burner

Question 7

The lowest temperature needed to kill or inactivate all microbes in 10 minutes is the

Accepted Answer

A) thermal death point (TDP). 
B) thermal death time (TDT). 
C) sporicidal time. 
D) death phase point. 
A) thermal death point (TDP). 
B) thermal death time (TDT). 
C) sporicidal time. 
D) death phase point.

Question 8

Prions require more extensive methods of sterilization than are needed for bacterial endospores.

Accepted Answer

A) True 
 B)False

Question 9

Your aim is to sterilize prosthetic devices like heart valves and artificial joint structures before being used in the patient.Considering where they will be placed and the probable composition of the devices, what would be the best chemical to use?

Accepted Answer

A)  Crystal violet dye 
B)  Iodine 
C)  Quaternary ammonium compounds 
D)  Bleach 
A)  Crystal violet dye 
B)  Iodine 
C)  Quaternary ammonium compounds 
D)  Bleach

Question 10

Which of the following is an advantage to using phenolics as antimicrobial agents?

Accepted Answer

A) The presence of organic matter does not limit its antimicrobial qualities. 
B) They are not susceptible to resistance by organisms. 
C) They have low toxicity. 
D) They are effective sterilants against all microbial forms. 
A) The presence of organic matter does not limit its antimicrobial qualities. 
B) They are not susceptible to resistance by organisms. 
C) They have low toxicity. 
D) They are effective sterilants against all microbial forms.

Question 11

Agents that can denature microbial proteins include all of the following except ______.

Accepted Answer

A) moist heat 
B) alcohol 
C) acids 
D) metallic ions 
E) X rays 
A) moist heat 
B) alcohol 
C) acids 
D) metallic ions 
E) X rays

Question 12

The easiest microbial forms to kill or inhibit are ______.

Accepted Answer

A) naked viruses 
B) vegetative bacteria and fungi 
C) endospores 
D) protozoan cysts 
E) mycobacteria and staphylococci 
A) naked viruses 
B) vegetative bacteria and fungi 
C) endospores 
D) protozoan cysts 
E) mycobacteria and staphylococci

Question 13

The presence of organic matter such as saliva and pus can interfere with the actions of disinfectants.

Accepted Answer

A) True 
 B)False

Question 14

The use of chemical agents directly on exposed body surfaces to destroy or inhibit vegetative pathogens is ______.

Accepted Answer

A) disinfection 
B) sterilization 
C) antisepsis 
D) sanitization 
A) disinfection 
B) sterilization 
C) antisepsis 
D) sanitization

Question 15

The process that destroys or removes all microorganisms and microbial forms, including bacterial endospores, on inanimate objects is ______.

Accepted Answer

A) disinfection 
B) sterilization 
C) antisepsis 
D) sanitization 
E) degermation 
A) disinfection 
B) sterilization 
C) antisepsis 
D) sanitization 
E) degermation

Question 16

Soaps and detergents are very effective as sterilants.

Accepted Answer

A) True 
 B)False

Question 17

Isopropyl alcohol wiped across a skin site can sterilize it.

Accepted Answer

A) True 
 B)False

Question 18

You have some old plastic Petri dishes that you would like to use for pouring bacteriological agar plates.The only method of physical sterilization is ultraviolet radiation sterilization with your UV light (you cannot use the autoclave because it will disfigure and melt the plastic).After sterilizing the plates, pouring the sterilized agar medium, and then leaving the plates out at room temperature for a day or two to let them solidify and dry, you find contaminating bacterial colonies growing on the agar.Predict what has happened in this situation.

Accepted Answer

A) The room temperature enhanced the growth of normal biota of the agar. 
B) Air got into the poured agar plates, contaminating them. 
C) The lids of the Petri dishes were inadvertently left on while being sterilized. 
D) The agar had bacteria in it, even after sterilization in the autoclave. 
A) The room temperature enhanced the growth of normal biota of the agar. 
B) Air got into the poured agar plates, contaminating them. 
C) The lids of the Petri dishes were inadvertently left on while being sterilized. 
D) The agar had bacteria in it, even after sterilization in the autoclave.

Question 19

Antimicrobial agents can target the cell wall by

Accepted Answer

A) blocking its synthesis. 
B) digesting it. 
C) denaturing proteins. 
D) All of the choices are correct. 
A) blocking its synthesis. 
B) digesting it. 
C) denaturing proteins. 
D) All of the choices are correct.

Question 20

Cold temperatures are considered microbistatic, whereas excessive heat is considered microbicidal. This is due to the fact that

Accepted Answer

A) 	in cold temperatures, the energy of activation is not sufficient to drive chemical reactions regardless of the

presence of enzymes, whereas excessive heat denatures enzymes and/or incinerates the cell causing irreparable damage. 
B) 	 cold temperatures denature enzymes causing irreparable damage to the cell, whereas heat limits the energy of activation available to drive chemical reactions. 
C) 	cold temperatures freeze and therefore kill the cell, whereas excess heat keeps the cell metabolically active but not dividing. 
D) 	cold temperatures halt binary fission and is therefore considered a sterilant, whereas heat does not kill spores so . it is not an effective method of control 
A) 	in cold temperatures, the energy of activation is not sufficient to drive chemical reactions regardless of the

presence of enzymes, whereas excessive heat denatures enzymes and/or incinerates the cell causing irreparable damage. 
B) 	 cold temperatures denature enzymes causing irreparable damage to the cell, whereas heat limits the energy of activation available to drive chemical reactions. 
C) 	cold temperatures freeze and therefore kill the cell, whereas excess heat keeps the cell metabolically active but not dividing. 
D) 	cold temperatures halt binary fission and is therefore considered a sterilant, whereas heat does not kill spores so . it is not an effective method of control

Exam 11: Physical and Chemical Control of Microbes

Each of the following is a target of antimicrobial agents except ______.

Which is correct regarding the rate of microbial death?

Which of the following is not a primary target of milk pasteurization?

Endospores can be inactivated by

All of the following are alkylating control agents except ______.

What instrument is most effective for pressure-temperature sterilization?

The lowest temperature needed to kill or inactivate all microbes in 10 minutes is the

Prions require more extensive methods of sterilization than are needed for bacterial endospores.

Your aim is to sterilize prosthetic devices like heart valves and artificial joint structures before being used in the patient.Considering where they will be placed and the probable composition of the devices, what would be the best chemical to use?

Which of the following is an advantage to using phenolics as antimicrobial agents?

Agents that can denature microbial proteins include all of the following except ______.

The easiest microbial forms to kill or inhibit are ______.

The presence of organic matter such as saliva and pus can interfere with the actions of disinfectants.

The use of chemical agents directly on exposed body surfaces to destroy or inhibit vegetative pathogens is ______.

The process that destroys or removes all microorganisms and microbial forms, including bacterial endospores, on inanimate objects is ______.

Soaps and detergents are very effective as sterilants.

Isopropyl alcohol wiped across a skin site can sterilize it.

Antimicrobial agents can target the cell wall by

Cold temperatures are considered microbistatic, whereas excessive heat is considered microbicidal. This is due to the fact that

The Main Themes of Microbiology

The Chemistry of Biology

Tools of the Laboratory: Methods for the Culturing of Microscopic Analysis of Microorganisms

Bacteria and Archaea

Eukaryotic Cells and Microorganisms

An Introduction to the Viruses

Microbial Nutrition, Ecology, and Growth

Microbial Metabolism: The Chemical Crossroads of Life

Microbial Genetics

Genetic Engineering and Recombinant Dna

Antimicrobial Treatment

Microbe-Human Interactions: Health and Disease

Host Defenses I: Overview and Nonspecific Defenses

Host Defenses II: Specific Immunity and Immunization

Disorders in Immunity

Diagnosing Infections

Infectious Diseases Affecting the Skin and Eyes

Infectious Diseases Affecting the Nervous System

Infectious Diseases Affecting the Cardiovascular and Lymphatic Systems

Infectious Diseases Affecting the Respiratory System

Infectious Diseases Affecting the Gastrointestinal Tract

Infectious Diseases Affecting the Genitourinary System

Microbes and the Environment

Applied Microbiology and Food and Water Safety

Filters