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BIOD 171 MODULE 3 EXAM Questions with
Correct Answers | Updated (100% Correct
Answers)
A nanometer is defined as: Answer: 10 -9 or one-billionth of a
meter
True or False: A nanometer is longer than a micrometer Answer:
False
A nanometer is 1000x smaller than a micrometer
Resolution and contrast are two critical factors that influence your
ability to see an object. Explain each. Answer: Resolution refers to
the distance between two objects at which the objects can still be
seen as separate. Poor or low resolution means two or more objects
may appear as one.
Contrast on the other hand is the difference in light absorbance
between two objects. Poor contrast gives a high background and
makes the visualization of multiple objects difficult. For instance,
trying to identify 2 dark colored objects at
night (low light = low contrast) versus the same 2 objects in the
middle of
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, 2
a sunny afternoon (bright light against 2 dark objects = high
contrast).
Assuming a fixed ocular, identify the part of the microscope you
would adjust to enhance the magnification of a sample. Answer:
Objective
Only the oculars (eyepiece) and the objectives contribute to the
magnification of the sample. Since the eyepiece
is fixed, only the objectives could be altered.
Assuming a constant (non-adjustable) light source power, identify
the part of the microscope you would adjust to limit the amount of
light entering the microscope. Answer: Iris diaphragm
What is the total magnification on (relative to your eye) of a sample
imaged with a 60x objective and a 10x eyepiece? Show your math.
Answer: 60x objective x 10x ocular = 600x magnification
True or False: Staining is often required to image a cell that is
adherent and flat (thin). Answer: True
Adherent, flat and unstained cells are almost invisible due to the
limits on both
resolution and contrast. Therefore, cell staining is often required to
adequately image
© 2025 All rights reserved
BIOD 171 MODULE 3 EXAM Questions with
Correct Answers | Updated (100% Correct
Answers)
A nanometer is defined as: Answer: 10 -9 or one-billionth of a
meter
True or False: A nanometer is longer than a micrometer Answer:
False
A nanometer is 1000x smaller than a micrometer
Resolution and contrast are two critical factors that influence your
ability to see an object. Explain each. Answer: Resolution refers to
the distance between two objects at which the objects can still be
seen as separate. Poor or low resolution means two or more objects
may appear as one.
Contrast on the other hand is the difference in light absorbance
between two objects. Poor contrast gives a high background and
makes the visualization of multiple objects difficult. For instance,
trying to identify 2 dark colored objects at
night (low light = low contrast) versus the same 2 objects in the
middle of
© 2025 All rights reserved
, 2
a sunny afternoon (bright light against 2 dark objects = high
contrast).
Assuming a fixed ocular, identify the part of the microscope you
would adjust to enhance the magnification of a sample. Answer:
Objective
Only the oculars (eyepiece) and the objectives contribute to the
magnification of the sample. Since the eyepiece
is fixed, only the objectives could be altered.
Assuming a constant (non-adjustable) light source power, identify
the part of the microscope you would adjust to limit the amount of
light entering the microscope. Answer: Iris diaphragm
What is the total magnification on (relative to your eye) of a sample
imaged with a 60x objective and a 10x eyepiece? Show your math.
Answer: 60x objective x 10x ocular = 600x magnification
True or False: Staining is often required to image a cell that is
adherent and flat (thin). Answer: True
Adherent, flat and unstained cells are almost invisible due to the
limits on both
resolution and contrast. Therefore, cell staining is often required to
adequately image
© 2025 All rights reserved
