Question 1

A reducing medium contains

Accepted Answer

A)  sugars that can be fermented. 
B)  extra oxygen. 
C)  hemoglobin, vitamins, or other growth factors. 
D)  substances that remove oxygen. 
E)  inhibiting agents. 
A)  sugars that can be fermented. 
B)  extra oxygen. 
C)  hemoglobin, vitamins, or other growth factors. 
D)  substances that remove oxygen. 
E)  inhibiting agents. D

Question 2

Explain the difference and significance between a contaminated culture and a mixed culture.

Accepted Answer

A contaminated culture refers to a culture that has been unintentionally contaminated with microorganisms from the environment, such as bacteria, fungi, or other contaminants. This can occur during the process of inoculating the culture or due to improper handling or sterilization techniques. Contaminated cultures can lead to inaccurate results and can compromise the integrity of the experiment or study being conducted.

On the other hand, a mixed culture refers to a culture that contains more than one type of microorganism. This can occur intentionally, such as when studying the interactions between different species, or unintentionally, such as when a culture becomes contaminated. Mixed cultures can be significant in research and clinical settings as they can provide insight into how different microorganisms interact and compete with each other.

The significance of distinguishing between contaminated and mixed cultures lies in the accuracy and reliability of the results obtained from the culture. Contaminated cultures can lead to false conclusions and unreliable data, while mixed cultures can provide valuable information about microbial interactions. Proper handling and sterilization techniques are essential to prevent contamination and ensure the integrity of the culture being studied.

Question 3

Brain-heart infusion, trypticase soy agar TSA), and nutrient agar are all examples of which type of media?

Accepted Answer

A)  synthetic 
B)  reducing 
C)  enriched 
D)  complex 
E)  selective 
A)  synthetic 
B)  reducing 
C)  enriched 
D)  complex 
E)  selective D

Question 4

Which of the following magnifies the specimen to produce the real image of the specimen?

Accepted Answer

A)  condenser 
B)  objective lens 
C)  ocular lens 
D)  body 
E)  nosepiece 
A)  condenser 
B)  objective lens 
C)  ocular lens 
D)  body 
E)  nosepiece

Question 5

Which microscope achieves the greatest resolution and highest magnification?

Accepted Answer

A)  bright-field 
B)  dark-field 
C)  phase-contrast 
D)  fluorescence 
E)  electron 
A)  bright-field 
B)  dark-field 
C)  phase-contrast 
D)  fluorescence 
E)  electron

Question 6

A media is designed that allows only staphylococci to grow. In addition, S. aureus colonies have a yellow halo around them and other staphylococci appear white. This type of media is

Accepted Answer

A)  selective only. 
B)  differential only. 
C)  both selective and differential. 
D)  a reducing media. 
E)  enriched. 
A)  selective only. 
B)  differential only. 
C)  both selective and differential. 
D)  a reducing media. 
E)  enriched.

Question 7

Compare and contrast the reagents and functions of negative staining versus positive staining.

Accepted Answer

Negative staining and positive staining

Question 8

Mannitol salt agar is selective for which bacterial genus?

Accepted Answer

A)  Salmonella 
B)  Streptococcus 
C)  Neisseria 
D)  Staphylococcus 
E)  Escherichia 
A)  Salmonella 
B)  Streptococcus 
C)  Neisseria 
D)  Staphylococcus 
E)  Escherichia

Question 9

All of the following are diameters of cells that would be resolved in a microscope with a limit of resolution of 0.2 µm except

Accepted Answer

A)  0.2 µm. 
B)  0.2 mm. 
C)  0.1 µm. 
D)  0.3 µm. 
E)  2.0 µm. 
A)  0.2 µm. 
B)  0.2 mm. 
C)  0.1 µm. 
D)  0.3 µm. 
E)  2.0 µm.

Question 10

A contaminated food sample contains several different species of bacteria. A food microbiologist is interested in studying just one of these species. Describe the sequence of procedures that the microbiologist must perform in order to obtain a pure culture of the bacterial species of interest from this food sample. Detail all the necessary media and equipment.

Accepted Answer

The microbiologist must first obtain a s

Question 11

The _____ of the microscope holds and allows selection of the objective lenses.

Accepted Answer

The answer of The _____ of the microscope holds and...

Question 12

A common medium used for growing fastidious bacteria is

Accepted Answer

A)  chocolate agar. 
B)  trypticase soy agar. 
C)  mannitol salt agar. 
D)  MacConkey medium. 
E)  a reducing medium. 
A)  chocolate agar. 
B)  trypticase soy agar. 
C)  mannitol salt agar. 
D)  MacConkey medium. 
E)  a reducing medium.

Question 13

A medium that is gel-like has less agar in it compared to a solid medium.

Accepted Answer

A) True 
 B)False

Question 14

Which type of medium is able to distinguish different species or types of microorganisms based on an observable change in the colonies or in the medium?

Accepted Answer

A)  differential 
B)  selective 
C)  enumeration 
D)  enriched 
E)  reducing 
A)  differential 
B)  selective 
C)  enumeration 
D)  enriched 
E)  reducing

Question 15

A pure culture contains only

Accepted Answer

A)  one species of microorganism. 
B)  bacteria. 
C)  a variety of microbes from one source. 
D)  All of these choices are correct. 
A)  one species of microorganism. 
B)  bacteria. 
C)  a variety of microbes from one source. 
D)  All of these choices are correct.

Question 16

The correct microbiological term for the tiny sample of specimen that is put into a nutrient medium in order to produce a culture is the _____.

Accepted Answer

The answer of The correct microbiological term for the tiny...

Question 17

Which of the following places the steps for microbial culture and identification in the correct order?

Accepted Answer

A)  inoculation, incubation, isolation, inspection, identification 
B)  isolation, inspection, inoculation, incubation, identification 
C)  incubation, inspection, isolation, identification, inoculation 
D)  inspection, identification, isolation, incubation, inoculation 
E)  inspection, isolation, incubation, inoculation, identification 
A)  inoculation, incubation, isolation, inspection, identification 
B)  isolation, inspection, inoculation, incubation, identification 
C)  incubation, inspection, isolation, identification, inoculation 
D)  inspection, identification, isolation, incubation, inoculation 
E)  inspection, isolation, incubation, inoculation, identification

Question 18

Which of the following characteristics refers to the microscope's ability to show two separate entities as separate and distinct?

Accepted Answer

A)  resolving power 
B)  magnification 
C)  refraction 
D)  All of these choices are correct. 
A)  resolving power 
B)  magnification 
C)  refraction 
D)  All of these choices are correct.

Question 19

The primary purpose of staining cells on a microscope slide is to

Accepted Answer

A)  kill them. 
B)  secure them to the slide. 
C)  enlarge the cells. 
D)  add contrast in order to see them better. 
E)  see motility. 
A)  kill them. 
B)  secure them to the slide. 
C)  enlarge the cells. 
D)  add contrast in order to see them better. 
E)  see motility.

Question 20

Bacteria that require special growth factors and complex nutrients are termed _____.

Accepted Answer

The answer of Bacteria that require special growth factors and...

Exam 3: Tools of the Laboratory: Methods of Studying Microorganisms

A reducing medium contains

Explain the difference and significance between a contaminated culture and a mixed culture.

Brain-heart infusion, trypticase soy agar TSA), and nutrient agar are all examples of which type of media?

Which of the following magnifies the specimen to produce the real image of the specimen?

Which microscope achieves the greatest resolution and highest magnification?

A media is designed that allows only staphylococci to grow. In addition, S. aureus colonies have a yellow halo around them and other staphylococci appear white. This type of media is

Compare and contrast the reagents and functions of negative staining versus positive staining.

Mannitol salt agar is selective for which bacterial genus?

All of the following are diameters of cells that would be resolved in a microscope with a limit of resolution of 0.2 µm except

The _____ of the microscope holds and allows selection of the objective lenses.

A common medium used for growing fastidious bacteria is

A medium that is gel-like has less agar in it compared to a solid medium.

Which type of medium is able to distinguish different species or types of microorganisms based on an observable change in the colonies or in the medium?

A pure culture contains only

The correct microbiological term for the tiny sample of specimen that is put into a nutrient medium in order to produce a culture is the _____.

Which of the following places the steps for microbial culture and identification in the correct order?

Which of the following characteristics refers to the microscope's ability to show two separate entities as separate and distinct?

The primary purpose of staining cells on a microscope slide is to

Bacteria that require special growth factors and complex nutrients are termed _____.

The Main Themes of Microbiology

The Chemistry of Biology

A Survey of Prokaryotic Cells and Microorganisms

A Survey of Eukaryotic Cells and Microorganisms

An Introduction to Viruses

Microbial Nutrition, Ecology, and Growth

An Introduction to Microbial Metabolism: the Chemical Crossroads of Life

Microbial Genetics

Genetic Engineering: a Revolution in Molecular Biology

Physical and Chemical Agents for Microbial Control

Drugs, Microbes, Host--The Elements of Chemotherapy

Microbe-Human Interactions: Infection and Disease

An Introduction to Host Defenses and Innate Immunities

Adaptive, Specific Immunity and Immunization

Disorders in Immunity

Procedures for Identifying Pathogens and Diagnosing Infections

The Gram-Positive and Gram-Negative Cocci of Medical Importance

The Gram-Positive Bacilli of Medical Importance

The Gram-Negative Bacilli of Medical Importance

Miscellaneous Bacterial Agents of Disease

The Fungi of Medical Importance

The Parasites of Medical Importance

Introduction to Viruses That Infect Humans: the Dna Viruses

The Rna Viruses That Infect Humans

Environmental Microbiology

Applied and Industrial Microbiology

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