Microscopy, Staining & Classifying
If you wanted to determine if a microorganism fermented a particular carbohydrate, which of the
following kinds of tests would you use?
A. serology
B. biochemical tests
C. morphology
D. phage typing
Put the following units of measurement in order, from largest to smallest:
I. Millimeter
II. Centimeter
III. Micrometer
IV. Meter
V. Nanometer
A. IV, II, I, III, V
B. V, III, II, I, IV
C. V, III, I, II, IV
D. III, V, I, II, IV
Which of the following has the shortest wavelength?
A. white light
B. violet light
C. red light
D. an electron beam
In microscopy, which of the following plays an important role in visualizing extremely small objects
clearly?
A. wavelength of radiation used
B. numerical aperture of the lens
C. contrast between the specimen and its background
D. Both A and C are correct.
E. Answers A, B, and C are correct.
Which of the following types of microscope is being used to examine the relationships between
microbes in biofilms on stromatolites?
A. scanning tunneling
B. confocal
C. scanning electron
D. transmission electron
All of the following are components of a bright-field compound microscope EXCEPT:
A. the oil immersion objective lens.
B. the condenser lens.
C. the scanning objective lens.
D. the phase plate.
The limit of useful magnification for a light microscope is
A. 100X.
B. 2000X.
C. 10,000X.
D. 1000X.
All of the following types of microscope can be used to view living specimens EXCEPT
A. a dark-field microscope.
B. an electron microscope.
C. a bright-field microscope.
D. an atomic force microscope.
Which of the following stains is used for visualizing Mycobacterium?
A. Acid-fast stain
B. Negative stain
C. Endospore stain
D. Gram stain
In the Gram stain, crystal violet serves as the
A. counterstain.
B. mordant.
C. primary stain.
D. decolorizing agent.
In the Gram stain, which of the reagents actually differentiates between Gram positive and Gram
negative cells?
A. Iodine
B. Ethanol/acetone
C. Crystal violet
D. Safranin
All of the following statements concerning taxonomy are true EXCEPT:
A. Each taxon includes all of the taxa above it.
B. All taxa have Latin names.
C. Species of asexual organisms are defined as collections of strains.
D. The genus name and the specific epithet together are called a binomial.
The designation E. coli O157:H7 is a result of which type of microbial identification process?
A. biochemical tests
B. phage typing
C. serology
D. morphology
The domain, a taxon proposed by Carl Woese, contains or replaces which of the following taxonomic
groups?
A. the phylum
B. the kingdom
C. the order
D. the genus
Which of the following taxonomic groupings was NOT part of the traditional Linnaean system of
classification?
A. subspecies
B. class
C. genus
D. family
Which of the following staining procedures is useful for visualizing endospores?
A. Schaeffer-Fulton
B. Gram
C. Ziehl-Neelsen
D. Osmium tetraoxide
Which of the following combinations would give the best microscopic resolution?
A. Large numerical aperture lens, short wavelength radiation
B. Small numerical aperture lens, short wavelength radiation
C. Small numerical aperture lens, long wavelength radiation
D. Large numerical aperture lens, long wavelength radiation
All of the following are aspects of scanning electron microscopy EXCEPT:
A. Secondary electrons are used to visualize the specimen.
B. Scanning electron micrographs typically appear two-dimensional.
C. Specimens must be placed into a vacuum.
D. Whole specimens can be observed.
Which of the following is a true statement concerning basic dyes?
A. Eosin is an example of a basic dye.
B. Basic dyes are also known as anionic chromophores.
C. Basic dyes work best at a low pH.
D. Basic dyes are attracted to the negatively-charged surface of cells.
What is the purpose of fixation in smear preparation?
A. It keeps cells from drying out during staining.
B. It enables cells to take up more stain.
C. It attaches cells firmly to the slide's surface.
D. It temporarily keeps cells from growing.