Portage Microbiology Lecture Exam 3
Questions and Answers Graded A+
micrometer - Correct answer-one millionth of a meter
nanometer - Correct answer-one billionth of a meter
two critical factors that influence our ability to see an object - Correct answer-
resolution and contrast
resolution - Correct answer-the distance between two objects at which the objects
still can be seen as separate
contrast - Correct answer-the difference in light absorbance between two (objects)
the closer two objects are to each other the __________________ the resolution
requirement - Correct answer-greater
the ________________ the contrast between an object and its background, the
harder it will be to see the object - Correct answer-lower
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, bright field microscope - Correct answer-simplest form of light, or optical,
microscopy/light, most often emitted from a standard halogen bulb, enters the
microscope from the base (bottom) and is reflected via mirrors towards the sample
before the light reaches the sample, it first passes through a ________________
converging the light beams into a focused area on the sample - Correct answer-
condenser
iris diaphragm - Correct answer-controls the amount of light that passes through
the sample and into the objective lens
objective lens - Correct answer-the lens closest to the sample and yields the
greatest amount of magnification
the degree of magnification is ______________________ to the amount of light
needed/to image samples clearly at higher magnifications, more light is required -
Correct answer-directly proportional
ocular lens - Correct answer-eyepiece
10x - Correct answer-most common power of ocular lens
total magnification - Correct answer-objective x ocular lens=
staining - Correct answer-required due to the limitation of resolution on unstained
cells, (i.e.) often the flat and transparent regions of a cell may appear invisible
©COPYRIGHT 2025, ALL RIGHTS RESERVED 2
Questions and Answers Graded A+
micrometer - Correct answer-one millionth of a meter
nanometer - Correct answer-one billionth of a meter
two critical factors that influence our ability to see an object - Correct answer-
resolution and contrast
resolution - Correct answer-the distance between two objects at which the objects
still can be seen as separate
contrast - Correct answer-the difference in light absorbance between two (objects)
the closer two objects are to each other the __________________ the resolution
requirement - Correct answer-greater
the ________________ the contrast between an object and its background, the
harder it will be to see the object - Correct answer-lower
©COPYRIGHT 2025, ALL RIGHTS RESERVED 1
, bright field microscope - Correct answer-simplest form of light, or optical,
microscopy/light, most often emitted from a standard halogen bulb, enters the
microscope from the base (bottom) and is reflected via mirrors towards the sample
before the light reaches the sample, it first passes through a ________________
converging the light beams into a focused area on the sample - Correct answer-
condenser
iris diaphragm - Correct answer-controls the amount of light that passes through
the sample and into the objective lens
objective lens - Correct answer-the lens closest to the sample and yields the
greatest amount of magnification
the degree of magnification is ______________________ to the amount of light
needed/to image samples clearly at higher magnifications, more light is required -
Correct answer-directly proportional
ocular lens - Correct answer-eyepiece
10x - Correct answer-most common power of ocular lens
total magnification - Correct answer-objective x ocular lens=
staining - Correct answer-required due to the limitation of resolution on unstained
cells, (i.e.) often the flat and transparent regions of a cell may appear invisible
©COPYRIGHT 2025, ALL RIGHTS RESERVED 2
