Question 1

Which microscope is most useful for visualizing a biofilm?

Accepted Answer

A)  scanning acoustic microscope 
B)  fluorescence microscope 
C)  phase- contrast microscope 
D)  transmission electron microscope 
E)  compound light microscope 
A)  scanning acoustic microscope 
B)  fluorescence microscope 
C)  phase- contrast microscope 
D)  transmission electron microscope 
E)  compound light microscope

Question 2

In a completed Gram stain, gram- positive bacteria are purple.

Accepted Answer

A) True 
 B)False

Question 3

Which of the following pairs is mismatched?

Accepted Answer

A)  methylene blue - simple stain 
B)  nigrosin - negative stain 
C)  basic dye - negative stain 
D)  acidic dye - capsule stain 
E)  crystal violet - simple stain 
A)  methylene blue - simple stain 
B)  nigrosin - negative stain 
C)  basic dye - negative stain 
D)  acidic dye - capsule stain 
E)  crystal violet - simple stain

Question 4

A virus measures 100 nm in length. What is its length in µm?

Accepted Answer

A)  0.01 µm 
B)  1 µm 
C)  0.001 µm 
D)  10 µm 
E)  .1 µm 
A)  0.01 µm 
B)  1 µm 
C)  0.001 µm 
D)  10 µm 
E)  .1 µm

Question 5

You are performing a Gram stain on gram- negative bacteria and you stop after the decolorizer step. What is the appearance of the bacteria at this point?

Accepted Answer

A)  purple 
B)  brown 
C)  colorless 
D)  red 
A)  purple 
B)  brown 
C)  colorless 
D)  red

Question 6

Which step in the Gram stain is the critical step in differentiating gram- positive cells from gram- negative cells?

Accepted Answer

A)  alcohol- acetone 
B)  iodine 
C)  crystal violet 
D)  safranin 
A)  alcohol- acetone 
B)  iodine 
C)  crystal violet 
D)  safranin

Question 7

Which microscope is used to observe a specimen that emits light when illuminated with an ultraviolet light?

Accepted Answer

A)  phase- contrast microscope 
B)  darkfield microscope 
C)  electron microscope 
D)  fluorescence microscope 
E)  compound light microscope 
A)  phase- contrast microscope 
B)  darkfield microscope 
C)  electron microscope 
D)  fluorescence microscope 
E)  compound light microscope

Question 8

Which of the following places the steps in the correct sequence? 1- Staining 2- Making a smear 3- Fixing

Accepted Answer

A)  3- 2- 1 
B)  2- 3- 1 
C)  1- 3- 2 
D)  1- 2- 3 
E)  The order is unimportant. 
A)  3- 2- 1 
B)  2- 3- 1 
C)  1- 3- 2 
D)  1- 2- 3 
E)  The order is unimportant.

Question 9

Which of the following pairs is mismatched?

Accepted Answer

A)  safranin - acid dye 
B)  iodine - mordant 
C)  carbolfuchsin - basic dye 
D)  alcohol- acetone - decolorizer 
E)  crystal violet - basic dye 
A)  safranin - acid dye 
B)  iodine - mordant 
C)  carbolfuchsin - basic dye 
D)  alcohol- acetone - decolorizer 
E)  crystal violet - basic dye

Question 10

Both phase- contrast microscopy and differential interference contrast microscopy are used to view the internal structures of cells without staining.

Accepted Answer

A) True 
 B)False

Question 11

Which microscope uses visible light?

Accepted Answer

A)  fluorescence microscope 
B)  differential interference contrast microscope 
C)  scanning acoustic microscope 
D)  scanning electron microscope 
E)  confocal microscope 
A)  fluorescence microscope 
B)  differential interference contrast microscope 
C)  scanning acoustic microscope 
D)  scanning electron microscope 
E)  confocal microscope

Question 12

In using this microscope, the observer does NOT look directly at an image through a lens.

Accepted Answer

A)  phase- contrast microscope 
B)  fluorescence microscope 
C)  compound light microscope 
D)  darkfield microscope 
E)  electron microscope 
A)  phase- contrast microscope 
B)  fluorescence microscope 
C)  compound light microscope 
D)  darkfield microscope 
E)  electron microscope

Question 13

Cells viewed in darkfield microscopy appear similar to those stained with the negative stain.

Accepted Answer

A) True 
 B)False

Question 14

The limit of resolution of the compound microscope illuminated with visible light is approximately
0.2 µm.

Accepted Answer

A) True 
 B)False

Question 15

Which of the following is NOT true regarding the acid- fast stain?

Accepted Answer

A)  Acid- fast cells appear red in a completed acid- fast stain. 
B)  Acid- fast cells retain the primary dye after treatment with acid- alcohol. 
C)  It is used to identify members of the genus Mycobacterium. 
D)  Non- acid- fast microbes appear blue in a completed acid- fast stain. 
E)  If cells are acid- fast, they are gram- negative. 
A)  Acid- fast cells appear red in a completed acid- fast stain. 
B)  Acid- fast cells retain the primary dye after treatment with acid- alcohol. 
C)  It is used to identify members of the genus Mycobacterium. 
D)  Non- acid- fast microbes appear blue in a completed acid- fast stain. 
E)  If cells are acid- fast, they are gram- negative.

Question 16

The purpose of the ocular lens is to

Accepted Answer

A)  decrease the light. 
B)  improve resolution. 
C)  decrease the refractive index. 
D)  increase the light. 
E)  magnify the image from the objective lens. 
A)  decrease the light. 
B)  improve resolution. 
C)  decrease the refractive index. 
D)  increase the light. 
E)  magnify the image from the objective lens.

Question 17

Which microscope is used to see detail of a 300- nm virus?

Accepted Answer

A)  darkfield microscope 
B)  electron microscope 
C)  fluorescence microscope 
D)  DIC microscope 
E)  phase- contrast microscope 
A)  darkfield microscope 
B)  electron microscope 
C)  fluorescence microscope 
D)  DIC microscope 
E)  phase- contrast microscope

Exam 3: Observing Microorganisms Through a Microscope

Which microscope is most useful for visualizing a biofilm?

In a completed Gram stain, gram- positive bacteria are purple.

Which of the following pairs is mismatched?

A virus measures 100 nm in length. What is its length in µm?

You are performing a Gram stain on gram- negative bacteria and you stop after the decolorizer step. What is the appearance of the bacteria at this point?

Which step in the Gram stain is the critical step in differentiating gram- positive cells from gram- negative cells?

Which microscope is used to observe a specimen that emits light when illuminated with an ultraviolet light?

Which of the following places the steps in the correct sequence? 1- Staining 2- Making a smear 3- Fixing

Which of the following pairs is mismatched?

Both phase- contrast microscopy and differential interference contrast microscopy are used to view the internal structures of cells without staining.

Which microscope uses visible light?

In using this microscope, the observer does NOT look directly at an image through a lens.

Cells viewed in darkfield microscopy appear similar to those stained with the negative stain.

The limit of resolution of the compound microscope illuminated with visible light is approximately 0.2 µm.

Which of the following is NOT true regarding the acid- fast stain?

The purpose of the ocular lens is to

Which microscope is used to see detail of a 300- nm virus?

The Microbial World and You

Chemical Principles

Functional Anatomy of Prokaryotic and Eukaryotic Cells

Microbial Metabolism

Microbial Growth

The Control of Microbial Growth

Microbial Genetics

Biotechnology and Recombinant Dna

Classification of Microorganisms

The Prokaryotes: Domains Bacteria and Archaea

The Eukaryotes: Fungi, Algae, Protozoa, and Helminths

Viruses, Viroids, and Prions

Principles of Disease and Epidemiology

Microbial Mechanisms of Pathogenicity

Innate Immunity: Nonspecific Defenses of the Host

Adaptive Immunity: Specific Defenses of the Host

Practical Applications of Immunology

Disorders Associated With the Immune System

Antimicrobial Drugs

Microbial Diseases of the Skin and Eyes

Microbial Diseases of the Nervous System

Microbial Diseases of the Cardiovascular and Lymphatic Systems

Microbial Diseases of the Respiratory System

Microbial Diseases of the Digestive System

Microbial Diseases of the Urinary and Reproductive Systems

Environmental Microbiology

Applied and Industrial Microbiology

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