1
MMG 301 Exam 1 MSU Questions with
Correct Answers | Updated (100% Correct
Answers)
Coccus Answer: spherical cells
Diplococcus Answer: Pair of spherical cells (cocci)
Staphylococcus Answer: cluster of spherical cells (cocci)
Staphylococcus Answer: a genus of gram-positive bacteria that are
potential pathogens, causing local lesions and serious opportunistic
infections
Vibrio Answer: bean shaped bacteria
Bacillus Answer: Rod shaped bacteria
Magnification Answer: ocular x objective
Numerical Aperture Answer: a number that expresses the ability of
a lens to resolve fine detail in an object being observed. Stamped
on the side of a lens.
resolving power (resolution) Answer: ability to show detail
Lambda Answer: wavelength used for microscopy
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,2
oil immersion Answer: A technique used to increase the resolution
of a microscope by immersing both the objective lens and the
specimen in a transparent oil.
bright field microscopy Answer: generates a dark image of an
object over a light background
dark field microscopy Answer: shows the specimen against a dark
background and provides good resolution
phase contrast microscope Answer: An optical-microscopy
technique that converts phase shifts in light passing through a
transparent specimen to brightness changes in the image. Phase
shifts themselves are invisible, but become visible when shown as
brightness variations.
fluorescence microscopy Answer: uses a fluorescent dye that emits
fluorescence when illuminated with ultraviolet radiation
Simple Stains Answer: the use of a single stain, used with a bright
field microscope. Increases contrast to aid in visualization.
differential stain Answer: the use of multiple stains of different
colors to distinguish different types of microorganisms.
Gram stain Answer: A staining method that distinguishes between
two different kinds of bacterial cell walls.
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, 3
acid fast stain Answer: a differential stain used to identify bacteria
that are not decolorized by acid-alcohol, that are waxy.
Microscopes that use optical methods for contrast enhancement
and visualization Answer: Phase Contrast, Dark Field, Fluorescence
Phase Contrast Answer: improved contrast between unstained
(living) bacteria, ideal for examining cell morphology.
Dark Field Answer: uses a cardioid condenser that produces a
hollow cone of light, ideal for examining very thin cells like
spirochete syphilis
Excitation Answer: absorbing of light, leads to a shorter wavelength.
Emission Answer: emission of light at a longer wavelength.
autofluorescent Answer: have cell components that fluoresce, don't
need to be stained
transmission electron microscope Answer: A microscope that uses
an electron beam to study the internal structure of thinly sectioned
specimens. Has to be done in a vacuum because electrons won't be
able to travel thru the specimen. Cells need to be embedded into a
plastic and use heavy metal ions to provide contrast.
scanning electron microscope Answer: scans the surface of a
specimen with a beam of electrons 30 times/second, ideal for
© 2025 All rights reserved
MMG 301 Exam 1 MSU Questions with
Correct Answers | Updated (100% Correct
Answers)
Coccus Answer: spherical cells
Diplococcus Answer: Pair of spherical cells (cocci)
Staphylococcus Answer: cluster of spherical cells (cocci)
Staphylococcus Answer: a genus of gram-positive bacteria that are
potential pathogens, causing local lesions and serious opportunistic
infections
Vibrio Answer: bean shaped bacteria
Bacillus Answer: Rod shaped bacteria
Magnification Answer: ocular x objective
Numerical Aperture Answer: a number that expresses the ability of
a lens to resolve fine detail in an object being observed. Stamped
on the side of a lens.
resolving power (resolution) Answer: ability to show detail
Lambda Answer: wavelength used for microscopy
© 2025 All rights reserved
,2
oil immersion Answer: A technique used to increase the resolution
of a microscope by immersing both the objective lens and the
specimen in a transparent oil.
bright field microscopy Answer: generates a dark image of an
object over a light background
dark field microscopy Answer: shows the specimen against a dark
background and provides good resolution
phase contrast microscope Answer: An optical-microscopy
technique that converts phase shifts in light passing through a
transparent specimen to brightness changes in the image. Phase
shifts themselves are invisible, but become visible when shown as
brightness variations.
fluorescence microscopy Answer: uses a fluorescent dye that emits
fluorescence when illuminated with ultraviolet radiation
Simple Stains Answer: the use of a single stain, used with a bright
field microscope. Increases contrast to aid in visualization.
differential stain Answer: the use of multiple stains of different
colors to distinguish different types of microorganisms.
Gram stain Answer: A staining method that distinguishes between
two different kinds of bacterial cell walls.
© 2025 All rights reserved
, 3
acid fast stain Answer: a differential stain used to identify bacteria
that are not decolorized by acid-alcohol, that are waxy.
Microscopes that use optical methods for contrast enhancement
and visualization Answer: Phase Contrast, Dark Field, Fluorescence
Phase Contrast Answer: improved contrast between unstained
(living) bacteria, ideal for examining cell morphology.
Dark Field Answer: uses a cardioid condenser that produces a
hollow cone of light, ideal for examining very thin cells like
spirochete syphilis
Excitation Answer: absorbing of light, leads to a shorter wavelength.
Emission Answer: emission of light at a longer wavelength.
autofluorescent Answer: have cell components that fluoresce, don't
need to be stained
transmission electron microscope Answer: A microscope that uses
an electron beam to study the internal structure of thinly sectioned
specimens. Has to be done in a vacuum because electrons won't be
able to travel thru the specimen. Cells need to be embedded into a
plastic and use heavy metal ions to provide contrast.
scanning electron microscope Answer: scans the surface of a
specimen with a beam of electrons 30 times/second, ideal for
© 2025 All rights reserved
