Deck 4: Microscopy, Staining, and Classification

Question 1

All of the following are components of electron microscopy stains EXCEPT:

A) lead.
B) eosin.
C) tungsten.
D) osmium.
E) uranium.

Answer 1

B

Question 2

A nanometer would be a suitable unit of measurement for which of the following?

A) eukaryotic cells
B) molecules and atoms
C) prokaryotic cells
D) bacterial colonies
E) cellular organelles and viruses

Answer 2

E

Question 3

The rules of naming organisms are called

A) taxonomy.
B) nomenclature.
C) identification.
D) binomials.
E) classification.

Answer 3

B

Question 4

If a microbiology lab technician left the crystal violet out of the Gram stain procedure, what would be the result?

A) All cells would be pink.
B) All cells would be purple.
C) Gram- positive cells would be pink and Gram- negative cells would be purple.
D) Gram- positive cells would be colorless and Gram- negative cells would be pink.
E) Gram- positive cells would be purple and Gram- negative cells would be colorless.

Question 5

Empty magnification results from increasing magnification without increasing the

A) refraction.
B) curvature of the lens.
C) resolution.
D) wavelength.
E) focal point.

Question 6

Cilia and flagella can be visualized using which of the following types of microscopes?

A) Nomarski microscopes
B) darkfield microscopes
C) phase- contrast microscopes
D) All of the above are correct.
E) None of the above is correct.

Question 7

Carbolfuchsin is used in which of the following staining procedures?

A) endospore stain
B) capsule stain
C) Gram stain
D) flagellar stain
E) acid- fast stain

Question 8

All of the following are kingdoms proposed by Robert Whitaker EXCEPT:

A) Protista.
B) Archaea.
C) Fungi.
D) Animalia.
E) Plantae.

Question 9

All of the following are common to both the Gram stain and the acid- fast stain EXCEPT:

A) counterstain.
B) primary stain.
C) a decolorizing agent and a mordant.
D) a mordant.
E) a decolorizing agent.

Question 10

A patient suffering from tuberculosis could be diagnosed by use of the _ stain.

A) acid- fast
B) Gram
C) capsule
D) flagellar
E) endospore

Question 11

All of the following are types of light microscopes EXCEPT:

A) fluorescent.
B) scanning tunneling.
C) bright- field.
D) confocal.
E) phase- contrast.

Question 12

Which of the following staining procedures uses heat to drive the stain into the cell?

A) acid- fast stain
B) endospore stain
C) capsule stain
D) Both A and B are correct.
E) A, B, and C are correct.

Question 13

Which of the following types of microscopes is capable of generating a three- dimensional image of a specimen?

A) scanning electron
B) differential interference contrast
C) confocal
D) Both B and C are correct.
E) A, B, and C are correct.

Question 14

Why does immersion oil improve resolution?

A) It increases the numerical aperture.
B) It decreases the working distance.
C) It allows light to travel at a uniform speed on its way to the lens.
D) Both A and C are correct.
E) A, B, and C are correct.

Question 15

Which of the following microscopes is capable of more than 100,000,000X magnification?

A) bright- field microscopes
B) scanning electron microscopes
C) differential interference contrast microscopes
D) scanning tunneling microscopes
E) transmission electron microscopes

Question 16

The numerical aperture of a lens refers to its

A) ability to gather light.
B) working distance.
C) resolution distance.
D) curvature.
E) thickness.

Question 17

The kingdoms included in the Linnaean system are:

A) Prokaryotae and Protista.
B) Animalia and Prokaryotae.
C) Fungi and Protista.
D) Animalia and Plantae.
E) Protista and Plantae.

Question 18

If you were trying to visualize flagella without staining, which microscope would you use?

A) dark- field
B) fluorescent
C) phase- contrast
D) confocal
E) bright- field

Question 19

All of the following are associated with an electron microscope EXCEPT:

A) a vacuum.
B) an electron beam.
C) a fluorescent screen.
D) a prism.
E) magnetic fields.

Question 20

The total magnification of a compound microscope is calculated using the magnification of which of the following?

A) the objective lens and the prism
B) the condenser and the ocular lenses
C) the condenser lens and the diaphragm
D) the objective and the ocular lenses
E) the objective and the condenser lense

Question 21

A resolution of 1 µm would be better than a resolution of 0.5 µm.

Question 22

Which of the following classification methods involves the use of antibodies to recognize different strains of a particular microbe?

A) biochemical tests
B) physical characteristics
C) serological tests
D) phage typing
E) analysis of nucleic acids

Question 23

A cell's GC ratio is associated with which of the following classification methods?

A) analysis of nucleic acids
B) biochemical tests
C) serological tests
D) phage typing
E) physical characteristics

Question 24

All of the following are characteristics of a genus name EXCEPT:

A) it is one of two names used to identify an organism.
B) it is either underlined or in italics.
C) it is usually an adjective.
D) it is written before the specific epithet.
E) it is always capitalized.

Question 25

The Gram stain works due to differences in the of bacteria.

A) cell membranes
B) capsules
C) genetic characteristics
D) antigens
E) cell walls

Question 26

The refraction of radiation as it passes through a lens creates which of the following?

A) resolving power
B) magnification
C) immunofluorescence
D) resolution distance
E) contrast

Question 27

All of the following types of microscopes are limited to magnification of about 2000X EXCEPT:

A) a dark- field microscope.
B) a differential interference contrast microscope.
C) a phase- contrast microscope.
D) a fluorescent microscope.
E) a scanning tunneling microscope.

Question 28

Linnaeus proposed the system of binomial nomenclature that we use today.

Question 29

Why is visible light relatively limited in its usefulness for microscopy?

A) Its wavelength is too long to enable high resolution of images.
B) It does not produce enough contrast in specimens.
C) It is not powerful enough to penetrate some specimens.
D) Both A and B are correct.
E) A, B, and C are correct.

Question 30

All of the following are associated with smear preparation EXCEPT:

A) spreading the specimen onto a slide.
B) killing the microbes in the specimen.
C) fixation using heat.
D) fixation using methanol or formalin.
E) agglutination of the specimen.

Question 31

Bacterial cells are so similar to each other that physical characteristics cannot be used in identification of organisms.

Question 32

The size of most cells is measured in

A) micrometers.
B) millimeters.
C) nanometers.
D) meters.
E) centimeters.

Question 33

A negative stain leaves cells colorless while staining the background of the smear.

Question 34

The three domains proposed by Carl Woese are the Archaea, the Eukarya, and the Bacteria.

Question 35

Basic dyes are more commonly used than acidic dyes because

A) they bind specifically to the lipid membrane of the cell.
B) they work best at a low pH.
C) they are best used for electron microscopy.
D) they fluoresce under UV light.
E) they are positively charged.

Question 36

Members of the genera Bacillus and Clostridium can be identified using the endospore stain.

Question 37

Carl Woese proposed the concept of the domain based on differences among which of the following cellular molecules?

A) membrane lipids
B) ribosomal RNA
C) proteins
D) DNA
E) transfer RNA

Question 38

A structure that appears in a transmission electron micrograph but which is not actually present in the specimen is known as a(n)

A) mordant.
B) biofilm.
C) artifact.
D) refraction.
E) antigen.

Question 39

Which of the following is NOT true of transmission electron microscopy?

A) Electrons are the source of illumination.
B) Thin segments must be used.
C) The sample is placed in a vacuum.
D) Glass lenses are used.
E) Stains can be applied to improve contrast.

Question 40

In the Linnaean system of taxonomy, an order is a subset of a larger taxonomic group called the

A) class.
B) kingdom.
C) phylum.
D) family.
E) genus.

Question 41

Light rays that are in phase reinforce each other and produce a brighter image.

Question 42

A(n) is a substance that binds to a dye and makes it less soluble.

Question 43

Carl Woese and his colleagues proposed the , a taxon that replaces the kingdom.

Question 44

An integral part of serological testing is the use of a solution called _ that contains antibodies.

Question 45

The total magnification using a 10X ocular and a 40X objective would be .

Question 46

The definitive reference work for the identification of bacteria is known as .

Question 47

A(n) is a clear area on a bacterial lawn that is evidence of virus growth.

Question 48

Light rays that pass through the edge of a curved lens will be refracted more than those that pass through the center.

Question 49

In taxonomy, organisms in similar classes can be classified in larger groups called _.

Question 50

In a compound microscope, the lens that directs light through the specimen is the lens.

Question 51

is the process of immobilizing organisms on a glass slide through the application of either heat or chemicals.

Question 52

An agglutination test is an example of a(n) type of classification test.

Question 53

In the presence of a decolorizing agent, Gram- negative cells lose the color of the counterstain.

Question 54

Bacterial viruses that can be used to help classify different groups of bacteria are called _.

Question 55

Acid- fast cells such as Mycobacterium lose the color of the primary stain in the presence of hydrochloric acid.

Question 56

A staining procedure that uses more than one dye is called a(n) stain.

Question 57

A(n) microscope has a single ocular lens.

Question 58

Robert Whitaker first proposed a taxonomic approach that is based on kingdoms.

Question 59

A(n) _ molecule is one that absorbs invisible radiation and emits visible light.

Question 60

Discuss the ways in which light rays can be manipulated in order to increase resolution and/or contrast.

Question 61

List and explain five types of techniques that can be used to identify unknown microorganisms.

Question 62

Discuss the role of the decolorizing agent in differential staining procedures.

Question 63

Compare and contrast the light microscope with the electron microscope.

Question 64

Compare and contrast the three domains identified by Woese-Eukarya, Bacteria, and Archaea.