Question 1

Which of these numeric aperture and light combinations would give the best resolution?

Accepted Answer

A)  numeric aperture = 0.8, wavelength = 600 nm 
B)  numeric aperture = 0.8, wavelength = 500 nm 
C)  numeric aperture = 1.0, wavelength = 700 nm 
D)  numeric aperture = 1.0, wavelength = 600 nm 
E)  numeric aperture = 0.8, wavelength = 400 nm 
A)  numeric aperture = 0.8, wavelength = 600 nm 
B)  numeric aperture = 0.8, wavelength = 500 nm 
C)  numeric aperture = 1.0, wavelength = 700 nm 
D)  numeric aperture = 1.0, wavelength = 600 nm 
E)  numeric aperture = 0.8, wavelength = 400 nm

Question 2

Why are stains used in microscopy? Compare and contrast the stains used in light versus electron microscopy.

Accepted Answer

Stains are used to increase the contrast

Question 3

Atomic force microscopy measures ________ between a probe and an object to map the three-dimensional topography of a cell.

Accepted Answer

A)  hydrogen bonds 
B)  covalent interactions 
C)  van der Waals forces 
D)  pH changes 
E)  magnetic interactions 
A)  hydrogen bonds 
B)  covalent interactions 
C)  van der Waals forces 
D)  pH changes 
E)  magnetic interactions

Question 4

Fluorescent microscopy that absorbs light at 260m would MOST likely fluoresce at

Accepted Answer

A)  100 nm. 
B)  200 nm. 
C)  260 nm. 
D)  400 nm. 
E)  800 nm. 
A)  100 nm. 
B)  200 nm. 
C)  260 nm. 
D)  400 nm. 
E)  800 nm.

Question 5

List three different differential stains used in microbiology. What can be detected with each?

Accepted Answer

The most common differential stain is th

Question 6

What happens to an electron when excited by light at the excitation wavelength?

Accepted Answer

A)  It remains in the same orbital. 
B)  It moves to a lower energy orbital. 
C)  It moves to a higher energy orbital. 
D)  It emits a photon. 
E)  It is filtered. 
A)  It remains in the same orbital. 
B)  It moves to a lower energy orbital. 
C)  It moves to a higher energy orbital. 
D)  It emits a photon. 
E)  It is filtered.

Question 7

As lens strength increases, the light cone ________ and the lens must be ________ the object.

Accepted Answer

A)  narrows; nearer to 
B)  narrows; farther from 
C)  widens; nearer to 
D)  widens; farther from 
E)  widens; touching 
A)  narrows; nearer to 
B)  narrows; farther from 
C)  widens; nearer to 
D)  widens; farther from 
E)  widens; touching

Question 8

Which of these arranges the steps of the Gram stain into the correct order?

Accepted Answer

A)  iodine crystal violet decolorizer safranin 
B)  safranin decolorizer crystal violet iodine 
C)  crystal violet decolorizer iodine safranin 
D)  crystal violet decolorizer safranin iodine 
E)  crystal violet iodine decolorizer safranin 
A)  iodine crystal violet decolorizer safranin 
B)  safranin decolorizer crystal violet iodine 
C)  crystal violet decolorizer iodine safranin 
D)  crystal violet decolorizer safranin iodine 
E)  crystal violet iodine decolorizer safranin

Question 9

Resolution is the smallest distance by which two objects can be ________ and still be ________.

Accepted Answer

A)  magnified; seen 
B)  separated; distinguished 
C)  magnified; separated 
D)  distinguished; separated 
E)  magnified; distinguished 
A)  magnified; seen 
B)  separated; distinguished 
C)  magnified; separated 
D)  distinguished; separated 
E)  magnified; distinguished

Question 10

What molecule is shown below?

Accepted Answer

A)  GFP 
B)  FM4-64 
C)  DNA 
D)  RNA 
E)  DAPI 
A)  GFP 
B)  FM4-64 
C)  DNA 
D)  RNA 
E)  DAPI

Question 11

Explain why components from thermophilic bacteria take less X-ray damage than other bacteria.

Accepted Answer

There is always unavoidable deterioratio

Question 12

What happens if the wavelength of radiation is larger than the object being viewed?

Accepted Answer

A)  absorption 
B)  scattering 
C)  no resolution 
D)  refraction 
E)  resolution 
A)  absorption 
B)  scattering 
C)  no resolution 
D)  refraction 
E)  resolution

Question 13

The digitally combined images of cryo-EM can achieve resolution comparable to that of

Accepted Answer

A)  scanning electron microscopy. 
B)  transmission electron microscopy. 
C)  interference microscopy. 
D)  X-ray crystallography. 
E)  dark-field microscopy. 
A)  scanning electron microscopy. 
B)  transmission electron microscopy. 
C)  interference microscopy. 
D)  X-ray crystallography. 
E)  dark-field microscopy.

Question 14

What would happen if a lens had the same refractive index as air?

Accepted Answer

A)  Light would not pass through the lens. 
B)  The image would be magnified more than with a glass lens. 
C)  The image would be magnified, but the resolution would be less than with a glass lens. 
D)  The image would be magnified, and the resolution would be greater than with a glass lens. 
E)  The image would not be magnified. 
A)  Light would not pass through the lens. 
B)  The image would be magnified more than with a glass lens. 
C)  The image would be magnified, but the resolution would be less than with a glass lens. 
D)  The image would be magnified, and the resolution would be greater than with a glass lens. 
E)  The image would not be magnified.

Question 15

Label the condenser in the figure below.

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
E)  E 
A)  A 
B)  B 
C)  C 
D)  D 
E)  E

Question 16

Staining helps to visualize bacteria by increasing the

Accepted Answer

A)  size of the cells. 
B)  motility of the cells. 
C)  contrast of the image. 
D)  magnification of the image. 
E)  aberration of the image. 
A)  size of the cells. 
B)  motility of the cells. 
C)  contrast of the image. 
D)  magnification of the image. 
E)  aberration of the image.

Question 17

Increasing the refractive index of the medium between the object and the objective lens increases

Accepted Answer

A)  refraction. 
B)  reflection. 
C)  magnification. 
D)  resolution. 
E)  wavelength. 
A)  refraction. 
B)  reflection. 
C)  magnification. 
D)  resolution. 
E)  wavelength.

Question 18

Which of the following would be MOST appropriate to visualize viral particles being assembled inside an infected bacterial cell?

Accepted Answer

A)  dark-field microscopy 
B)  atomic force microscopy 
C)  fluorescence microscopy 
D)  scanning electron microscopy 
E)  transmission electron microscopy 
A)  dark-field microscopy 
B)  atomic force microscopy 
C)  fluorescence microscopy 
D)  scanning electron microscopy 
E)  transmission electron microscopy

Question 19

List and briefly describe four ways that light interacts with objects.

Accepted Answer

(1) Absorption: light energy is absorbed

Question 20

What is the best explanation for a Gram-negative bacterium appearing purple after performing a Gram stain?

Accepted Answer

A)  The safranin was not applied. 
B)  The decolorizer was not applied. 
C)  The iodine was not applied. 
D)  The crystal violet was not applied. 
E)  The stain was properly performed. 
A)  The safranin was not applied. 
B)  The decolorizer was not applied. 
C)  The iodine was not applied. 
D)  The crystal violet was not applied. 
E)  The stain was properly performed.

Exam 2: Observing the Microbial Cell

Which of these numeric aperture and light combinations would give the best resolution?

Why are stains used in microscopy? Compare and contrast the stains used in light versus electron microscopy.

Atomic force microscopy measures ________ between a probe and an object to map the three-dimensional topography of a cell.

Fluorescent microscopy that absorbs light at 260m would MOST likely fluoresce at

List three different differential stains used in microbiology. What can be detected with each?

What happens to an electron when excited by light at the excitation wavelength?

As lens strength increases, the light cone ________ and the lens must be ________ the object.

Which of these arranges the steps of the Gram stain into the correct order?

Resolution is the smallest distance by which two objects can be ________ and still be ________.

What molecule is shown below?

Explain why components from thermophilic bacteria take less X-ray damage than other bacteria.

What happens if the wavelength of radiation is larger than the object being viewed?

The digitally combined images of cryo-EM can achieve resolution comparable to that of

What would happen if a lens had the same refractive index as air?

Label the condenser in the figure below.

Staining helps to visualize bacteria by increasing the

Increasing the refractive index of the medium between the object and the objective lens increases

Which of the following would be MOST appropriate to visualize viral particles being assembled inside an infected bacterial cell?

List and briefly describe four ways that light interacts with objects.

What is the best explanation for a Gram-negative bacterium appearing purple after performing a Gram stain?

Microbial Life: Origin and Discovery

Cell Structure and Function

Bacterial Culture, Growth, and Development

Environmental Influences and Control of Microbial Growth

Viruses

Genomes and Chromosomes

Transcription, Translation, and Bioinformatics

Gene Transfer, Mutations, and Genome Evolution

Molecular Regulation

Viral Molecular Biology

Biotechniques and Synthetic Biology

Energetics and Catabolism

Electron Flow in Organotrophy, Lithotrophy, and Phototrophy

Biosynthesis

Food and Industrial Microbiology

Origins and Evolution

Bacterial Diversity

Archaeal Diversity

Eukaryotic Diversity

Microbial Ecology

Microbes in Global Elemental Cycles

Human Microbiota and Innate Immunity

The Adaptive Immune Response

Microbial Pathogenesis

Microbial Diseases

Antimicrobial Therapy

Clinical Microbiology and Epidemiology

Filters

As lens strength increases, the light cone and the lens must be the object.

Resolution is the smallest distance by which two objects can be and still be .