Deck 4: Microscopy

Question 1

Using the information from the image below, determine the magnification of the microbe.

A) 200X
B) 2.2X
C) 91X
D) 110X

Answer 1

D

Question 2

In the history of microscopy, who is considered the "Father of Microbiology"?

A) Hans Jansen
B) Zacharias Jansen
C) Antonie van Leeuwenhoek
D) Ernst Ruska

Answer 2

C

Question 3

What is the definition of the term magnification?

A) Ratio of the size of the bacterium to the size of the object.
B) Ratio of the size of the protozoan to the size of the objective.
C) Ratio of the size of the image to the size of the object.
D) Ratio of the size of the objective to the size of the microorganism.

Answer 3

C

Question 4

The iris diaphragm ________.

A) focuses light on specimen
B) separately magnify specimen
C) holds the specimen in place
D) controls light intensity via adjustable opening

Question 5

The condenser ________.

A) focuses light on specimen
B) separately magnify specimen
C) holds the specimen in place
D) controls light intensity via adjustable opening

Question 6

The ________ holds the specimen in place on a light microscope.

A) Iris diaphragm
B) Condenser lens
C) Objective and Ocular lenses
D) Stage

Question 7

The________ magnify the specimen on a light microscope.

A) Iris diaphragm
B) Condenser lens
C) Objective and Ocular lenses
D) Stage

Question 8

What is the correct order of microscope parts from the base to the ocular?

A) Base, illuminator, condenser lens, iris diaphragm, stage, objective lens, ocular lens
B) Base, condenser lens, illuminator, iris diaphragm, objective lens, stage, ocular lens
C) Base, iris diaphragm, stage, illuminator, condenser lens, objective lens, ocular lens
D) Base, stage, condenser lens, illuminator, objective lens, stage, iris diaphragm, ocular lens

Question 9

What two features of a microscope are essential for a microbiologist?

A) Magnification and resolution
B) Magnification and oil immersion
C) Resolution and oil immersion
D) Objectives and oculars

Question 10

Which of the following best defines the term "resolution"?

A) The degree to which a microscope shows two images very far apart
B) The degree to which a microscope shows two or more cells as being distinct
C) The degree to which a microscope shows two or more cells as being close together
D) The degree to which a microscope shows two very close objects as being separate and apart

Question 11

What is the effect of using immersion oil plus oil immersion objective? (Select all that apply)

A) Resolving power is increased because immersion oil has same refractive index as glass.
B) As light passes through the glass of the cover slip, oil and the glass of the oil immersion lens, there is no light lost as a result of differences in refractive index.
C) Increases both magnification and resolving power of microscope.
D) Magnification increases from 1000X to 4500X.

Question 12

The image below represents a(n): ________.

A) Dark field microscope
B) Bright field microscope
C) Fluorescence microscope
D) Phase contrast microscope

Question 13

A bright field microscope ________. (Select all that apply)

A) produces an image showing fluorescent portions of specimen
B) is the simplest, most common type of microscope
C) produces a bright image against dark background
D) produces the image of a stained specimen is visualized against a bright background

Question 14

What are the disadvantages of Bright-field microscopy? (Select all that apply)

A) Staining is required to make specimens visible
B) The limit for magnification is 1000X
C) Images of very small specimens show very little detail, just the overall organism structure
D) It is the simplest, most common type of microscope

Question 15

What type of microscope was used to produce the image below?

A) Dark field microscope
B) Bright field microscope
C) Fluorescence microscope
D) Phase contrast microscope

Question 16

A dark field microscope ________.

A) produces an image showing fluorescent portions of specimen
B) is the simplest, most common type of microscope
C) produces a bright image against dark background
D) produces the image of a stained specimen is visualized against a bright background

Question 17

What are the advantages of Dark-field microscopy? (Select all that apply)

A) It may be used for living microbes
B) It may be used for hard-to-stain microbes
C) It highlights only surfaces of microbes
D) It can be used to visualize very thin specimens

Question 18

What type of microscope is shown below?

A) Bright field microscope
B) Transmission electron microscope
C) Dark field microscope
D) Fluorescence microscope

Question 19

What dyes are used most often with fluorescence microscopy?

A) Malachite green and carbol fuchsin
B) Fluorescein and rhodamine
C) Fluorescein and crystal violet
D) Crystal violet and safranin

Question 20

Which of the following statements is TRUE concerning Direct Fluorescent Antibody (DFA) Assay use in microscopy? (Select all that apply)

A) Monoclonal antibodies bind to dyes and are then bound to pathogens
B) Antibody-dye conjugates glow under uv light and show presence of pathogen
C) Fluorescein and rhodamine are dyes most commonly used as they glow green and red
D) It is the simplest, most common type of microscope

Question 21

What type of microscope was used to produce the image below?

A) Differential interference contrast microscopy
B) Bright field microscope
C) Fluorescence microscope
D) Confocal microscope

Question 22

Confocal Microscopy: ________.

A) Uses an electrically charged nanoprobe to scan the surface of a metal-coated specimen
B) Produces a three-dimensional image by assembling scanned regions of a fluorescent specimen
C) Displays unstained cellular structures that are visualized using differences in refractive indices
D) An ultrathin specimen is penetrated by an electron beam to show very good magnification and detailed resolution

Question 23

Phase Contrast Microscopy: ________.

A) Uses an electrically charged nanoprobe to scan the surface of a metal-coated specimen
B) Produces a three-dimensional image by assembling scanned regions of a fluorescent specimen
C) Displays unstained cellular structures that are visualized using differences in refractive indices
D) An ultrathin specimen is penetrated by an electron beam to show very good magnification and detailed resolution

Question 24

What are the major characteristics of phase contrast microscopy? (Select all that apply)

A) The true structure of living specimens may be viewed without the potential distortion of staining.
B) It converts differences in refractive indices to differences in color via use of prisms.
C) Special filters convert differences in light that are out of phase with waves through background into differences in light intensity.
D) It increases the resolution limit of a confocal microscope.

Question 25

Differential Interference Contrast Microscopy (DIC) makes use of these features to enable microbiologists to view a living specimen: ________.

A) changes in light waves as they pass through the living specimen are out of phase with each other
B) utilizes a bright-field microscope with filters
C) Three-dimensional color images generated
D) Magnification is higher than that of a bright-field microscope

Question 26

What type of microscope is shown below?

A) Bright field microscope
B) Transmission electron microscope
C) Fluorescence microscope
D) Dark field microscope

Question 27

What type of microscope is shown below?

A) Dark field microscope
B) Transmission electron microscope
C) Scanning electron microscope
D) Fluorescence microscope

Question 28

An ultrathin specimen is penetrated by transmission of an electron beam to produce and image with high magnification and detailed resolution.

A) Confocal Microscopy
B) Phase Contrast Microscopy
C) Transmission Electron Microscopy
D) Scanning Electron Microscopy

Question 29

Electrons are scattered from the surface of a metal-coated specimen to generate a three-dimensional image with high magnification and detailed resolution.

A) Confocal Microscopy
B) Phase Contrast Microscopy
C) Transmission Electron Microscopy
D) Scanning Electron Microscopy

Question 30

What of the following is a correct statement about the major differences between electron and light microscopes? (Select all that apply)

A) Electron microscopes use beams of electrons and electromagnetic lenses while light microscopes use visible light waves and glass lenses.
B) Electron microscopes can show detailed images at the level of the cellular organelles while light microscopes cannot do this.
C) Electron microscopes have a lower resolving power that light microscopes because an electron bean has a longer wavelength that visible light.
D) Electron microscopes produces images on a photographic plate while light microscopes produce images through the ocular lens.

Question 31

What is the major difference between TEM and SEM?

A) TEM uses light waves and electrons while SEM uses only electron beams.
B) TEM uses electromagnetic condenser lens as well as an electromagnetic objective lens while SEM uses only 2 electromagnetic lenses.
C) TEM uses a projector lens while SEM uses a photomultiplier.
D) TEM projects a 2-dimensional cross section of a microbe while SEM projects a 3-dimensional image with surface details.

Question 32

Which of the following is a major characteristic of super-resolution microscopy? (Select all that apply)

A) It increases the resolution of transmission electron microscopy
B) It increases the resolution limit of a confocal microscope
C) It is able to produce an image in very low light
D) It can visualize living and dead cells

Question 33

The very complex microscopes used in research are classified according to ________.

A) how large and complex they are
B) how they generate a magnified image
C) type of stain required
D) whether they make use of probes

Question 34

What is the incorrect match below?

A) Light microscope/visible light and glass lenses.
B) Electron microscope/electron beam and electromagnetic lenses.
C) Nanoprobe microscope/ fine-tipped probes are used to penetrate the surface of a specimen to magnify internal structures.
D) Confocal microscope/illuminates one focal plane at a time which is then reassembled into a three-dimensional image.

Question 35

Which of the following statements about Scanning Tunneling Microscopy is correct? (Select all that apply)

A) It utilizes an electrically charged nanoprobe to scan surface of a metal-coated specimen.
B) It measures changes in voltage detected by the nanoprobe.
C) The voltage changes detected by the probe are converted to an image.
D) The resolution is not good enough to see anything at the atomic level.

Question 36

Which of the following statements about Atomic Force Microscopy is true? (Select all that apply)

A) A fine-tipped probe is dragged across surface of molecules like proteins.
B) The movements of probe are amplified to produce an image.
C) The heights of a structure can be delineated relative to the background.
D) The voltage changes detected by the probe are converted to an image.

Question 37

The bright field light micrograph below is an image of: ________.

A) gram positive bacterial cells
B) gram negative bacterial cells
C) acid fast bacterial cells
D) bacterial cells with endospores

Question 38

The bright field light micrograph below is an image of: ________.

A) gram positive bacterial cells
B) gram negative bacterial cells
C) acid fast bacterial cells
D) bacterial cells with endospores

Question 39

A 20-year-old male presented at the emergency room with intense burning during urination. A copious amount of pus was being discharged from his penis. A micrograph of a gram stain of the pus is shown below. The man is infected with ________.

A) gram negative bacteria that have infected leukocytes
B) gram positive bacteria that have infected leukocytes
C) gram positive bacteria and gram positive eukaryotic pathogens
D) gram negative bacteria and gram negative eukaryotic pathogens

Question 40

What is the correct order of steps in smear preparation?
1) Apply suspension of cells on slide
2) spread over surface of slide
3) heat fix or chemical fix specimen on slide
4) air dry

A) 1, 2, 4, 3
B) 1, 2, 3, 4
C) 1, 3, 2, 4
D) 3, 2, 1, 4

Question 41

Simple Stains have this characteristic: ________. (Select all that apply)

A) Only one dye is used
B) Staining will show size, shape and arrangement of cells
C) They use a decolorizer
D) they use a secondary stain

Question 42

Positive Staining technique: ________.

A) shows clear cells against a darkly stained background
B) uses stains that are acidic such as nigrosine and Indian ink
C) uses stains that have a negative charge that is repelled by the negative charge of cell surface carbohydrates and glycoproteins
D) uses basic dyes such as Methylene Blue and Crystal Violet

Question 43

Among the characteristics of Positive Staining are: ________. (Select all that apply)

A) cells are colored against a clear background
B) The positive charge of stain is attracted to negatively charges on DNA and surface proteins
C) examples include nigrosin and India ink
D) Examples include methylene blue and crystal violet

Question 44

Negative staining: ________. (Select all that apply)

A) shows clear cells against darkly stained background
B) uses stains that are acidic and have a negative charge
C) works because the negative charge is repelled by negative charge of carbs and glycoproteins on bacterial surfaces
D) shows stained cells against a clear background

Question 45

Differential staining requires: ________. (Select all that apply)

A) preparation of a smear
B) application of 2 or more different positive stains
C) decolorizing chemical
D) preparation of a hanging drop

Question 46

What is the primary stain used in the Gram stain?

A) Crystal violet
B) Safranin
C) Malachite Green
D) Methylene Blue

Question 47

What is the primary stain used in the Acid-Fast stain?

A) Crystal violet
B) Carbol fuchsin
C) Malachite Green
D) Methylene Blue

Question 48

What is the counter or secondary stain used in the Acid-Fast stain?

A) Crystal violet
B) Safranin
C) Carbol fuchsin
D) Methylene Blue

Question 49

The light micrograph below is an example of: ________.

A) A capsule stain
B) An acid fast stain
C) An endospore stain
D) Dark field microscopy

Question 50

The light micrograph below is an example of: ________.

A) A capsule stain
B) An acid fast stain
C) An endospore stain
D) A Gram stain

Question 51

Capsule staining shows ________ capsules surrounding ________ cells against a ________ background.

A) clear; colored; colored
B) colored; clear; colored
C) colored; colored; clear
D) clear; colored; clear

Question 52

Flagella staining requires ________ to make the flagella more visible.

A) dye only in a single layer
B) dye plus mordent in a single layer of dye
C) mordent only in a single layer
D) dye plus mordant in multiple layers

Question 53

What is the primary stain used in the endospore stain?

A) Safranin
B) Carbol fuchsin
C) Malachite Green
D) Methylene Blue