Question 1

In 1877, Robert Koch thought preparing permanently stained slides would be valuable. Why was his assessment correct?

Accepted Answer

In 1877, Robert Koch, a pioneering micro

Question 2

A microorganism measures 5 µm in length. Its length in mm would be

Accepted Answer

A)  50 mm. 
B)  0.005 mm. 
C)  0.5 mm. 
D)  500 mm. 
E)  0.05 mm. 
A)  50 mm. 
B)  0.005 mm. 
C)  0.5 mm. 
D)  500 mm. 
E)  0.05 mm.

Question 3

In 1884, Hans Christian Gram described a method of staining bacterial cells while not staining surrounding animal tissues. However, he thought that the staining method he developed was faulty because not all bacteria stained. In a letter to the editor of the journal in which Gram published his findings, write your response to Gram's concern.

Accepted Answer

Dear Hans Christian Gram,

I recently re

Question 4

Which of the following pairs is mismatched?

Accepted Answer

A)  confocal microscope -produces a three- dimensional image 
B)  fluorescence microscope -uses a fluorescent light 
C)  scanning electron microscope -produces a three- dimensional image 
D)  darkfield microscope -uses visible light 
E)  scanning tunneling microscope -allows visualization of atoms 
A)  confocal microscope -produces a three- dimensional image 
B)  fluorescence microscope -uses a fluorescent light 
C)  scanning electron microscope -produces a three- dimensional image 
D)  darkfield microscope -uses visible light 
E)  scanning tunneling microscope -allows visualization of atoms

Question 5

The capsules and flagella of bacteria can be observed in gram- stained smears.

Accepted Answer

A) True 
 B)False

Question 6

A student is looking at a bacterial specimen using the oil immersion lens, but has forgotten to put immersion oil on the slide. The specimen will appear

Accepted Answer

A)  larger than it would if immersion oil was used. 
B)  to have no color. 
C)  the same as it would if the immersion oil was used. 
D)  smaller than it would if immersion oil was used. 
E)  somewhat fuzzy and have poor resolution. 
A)  larger than it would if immersion oil was used. 
B)  to have no color. 
C)  the same as it would if the immersion oil was used. 
D)  smaller than it would if immersion oil was used. 
E)  somewhat fuzzy and have poor resolution.

Question 7

You find colorless areas in cells in a gram- stained smear. What should you apply next?

Accepted Answer

A)  an acid- fast stain 
B)  a flagella stain 
C)  a capsule stain 
D)  a simple stain 
E)  an endospore stain 
A)  an acid- fast stain 
B)  a flagella stain 
C)  a capsule stain 
D)  a simple stain 
E)  an endospore stain

Question 8

Scanned probe microscopy is used to examine fine detail of molecular complexes, such as blood clots, or molecules, such as DNA.

Accepted Answer

A) True 
 B)False

Question 9

The greater resolution of the electron microscope compared to the compound microscope is due to the longer wavelengths of the electrons used to examine specimens.

Accepted Answer

A) True 
 B)False

Question 10

Which microscope achieves the highest magnification and greatest resolution?

Accepted Answer

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

Question 11

You are performing a Gram stain on gram- positive bacteria and you stop after the addition of the first dye. What is the appearance of the bacteria at this point?

Accepted Answer

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

Question 12

What is the total magnification of a specimen viewed with a 10x ocular lens and a 45x objective lens?

Accepted Answer

A)  45x 
B)  100x 
C)  4.5x 
D)  10x 
E)  450x 
A)  45x 
B)  100x 
C)  4.5x 
D)  10x 
E)  450x

Question 13

Figure 3.1
  
-In Figure 3.1, line "c" points to the microscope's

Accepted Answer

A)  illuminator. 
B)  ocular lens. 
C)  objective lens. 
D)  condenser. 
A)  illuminator. 
B)  ocular lens. 
C)  objective lens. 
D)  condenser.

Question 14

What structure does light pass through after leaving the condenser in a compound light microscope?

Accepted Answer

A)  specimen 
B)  illuminator 
C)  objective lens 
D)  ocular lens 
A)  specimen 
B)  illuminator 
C)  objective lens 
D)  ocular lens

Question 15

Which microscope is used to see intracellular detail in a living cell?

Accepted Answer

A)  atomic force microscope 
B)  two- photon microscope 
C)  brightfield microscope 
D)  fluorescence microscope 
E)  transmission electron microscope 
A)  atomic force microscope 
B)  two- photon microscope 
C)  brightfield microscope 
D)  fluorescence microscope 
E)  transmission electron microscope

Question 16

Which microscope is used to observe viruses and the internal structure of thinly sectioned cells?

Accepted Answer

A)  fluorescence microscope 
B)  scanning electron microscope 
C)  brightfield microscope 
D)  transmission electron microscope 
E)  darkfield microscope 
A)  fluorescence microscope 
B)  scanning electron microscope 
C)  brightfield microscope 
D)  transmission electron microscope 
E)  darkfield microscope

Question 17

Which microscope uses two beams of light to produce a three- dimensional color image?

Accepted Answer

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

Question 18

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

Accepted Answer

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

Question 19

Which of the following correctly traces the path of light through the compound microscope?

Accepted Answer

A)  light source; condenser; objective lens; specimen; ocular lens 
B)  light source; condenser; specimen; objective lens; ocular lens 
C)  condenser; light source; specimen; objective lens; ocular lens 
D)  condenser; light source; specimen; ocular lens; objective lens 
E)  light source; specimen; condenser; objective lens; ocular lens 
A)  light source; condenser; objective lens; specimen; ocular lens 
B)  light source; condenser; specimen; objective lens; ocular lens 
C)  condenser; light source; specimen; objective lens; ocular lens 
D)  condenser; light source; specimen; ocular lens; objective lens 
E)  light source; specimen; condenser; objective lens; ocular lens

Question 20

Bacterial smears are fixed before staining to

Accepted Answer

A)  make the cells visible. 
B)  affix the cells to the slide. 
C)  make their walls permeable. 
D)  accept stain. 
A)  make the cells visible. 
B)  affix the cells to the slide. 
C)  make their walls permeable. 
D)  accept stain.

Exam 3: Observing Microorganisms Through a Microscope

In 1877, Robert Koch thought preparing permanently stained slides would be valuable. Why was his assessment correct?

A microorganism measures 5 µm in length. Its length in mm would be

Which of the following pairs is mismatched?

The capsules and flagella of bacteria can be observed in gram- stained smears.

A student is looking at a bacterial specimen using the oil immersion lens, but has forgotten to put immersion oil on the slide. The specimen will appear

You find colorless areas in cells in a gram- stained smear. What should you apply next?

Scanned probe microscopy is used to examine fine detail of molecular complexes, such as blood clots, or molecules, such as DNA.

The greater resolution of the electron microscope compared to the compound microscope is due to the longer wavelengths of the electrons used to examine specimens.

Which microscope achieves the highest magnification and greatest resolution?

You are performing a Gram stain on gram- positive bacteria and you stop after the addition of the first dye. What is the appearance of the bacteria at this point?

What is the total magnification of a specimen viewed with a 10x ocular lens and a 45x objective lens?

Figure 3.1 -In Figure 3.1, line "c" points to the microscope's

What structure does light pass through after leaving the condenser in a compound light microscope?

Which microscope is used to see intracellular detail in a living cell?

Which microscope is used to observe viruses and the internal structure of thinly sectioned cells?

Which microscope uses two beams of light to produce a three- dimensional color image?

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

Which of the following correctly traces the path of light through the compound microscope?

Bacterial smears are fixed before staining to

The Microbial World and You

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Functional Anatomy of Prokaryotic and Eukaryotic Cells

Microbial Metabolism

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The Control of Microbial Growth

Microbial Genetics

Biotechnology and Recombinant Dna

Classification of Microorganisms

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Viruses, Viroids, and Prions

Principles of Disease and Epidemiology

Microbial Mechanisms of Pathogenicity

Innate Immunity: Nonspecific Defenses of the Host

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Practical Applications of Immunology

Disorders Associated With the Immune System

Antimicrobial Drugs

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