BIOD 171 MODULE 3 EXAM WITH
CORRECT QUESTIONS AND ANSWERS
2025
A nanometer is defined as: - CORRECT-ANSWERS10 -9 or one-billionth of a
meter
True or False: A nanometer is longer than a micrometer - CORRECT-
ANSWERSFalse
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. - CORRECT-ANSWERSResolution 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
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. - CORRECT-ANSWERSObjective
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. - CORRECT-ANSWERSIris 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. - CORRECT-
ANSWERS60x objective x 10x ocular = 600x magnification
True or False: Staining is often required to image a cell that is adherent and
flat (thin). - CORRECT-ANSWERSTrue
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
the sample.
True or False: A cell that is adherent, flat (thin), and unstained is easily
identified using bright field microscopy - CORRECT-ANSWERSFalse: Adherent,
flat cells are almost invisible due to the limits on both resolution and contrast
CORRECT QUESTIONS AND ANSWERS
2025
A nanometer is defined as: - CORRECT-ANSWERS10 -9 or one-billionth of a
meter
True or False: A nanometer is longer than a micrometer - CORRECT-
ANSWERSFalse
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. - CORRECT-ANSWERSResolution 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
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. - CORRECT-ANSWERSObjective
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. - CORRECT-ANSWERSIris 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. - CORRECT-
ANSWERS60x objective x 10x ocular = 600x magnification
True or False: Staining is often required to image a cell that is adherent and
flat (thin). - CORRECT-ANSWERSTrue
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
the sample.
True or False: A cell that is adherent, flat (thin), and unstained is easily
identified using bright field microscopy - CORRECT-ANSWERSFalse: Adherent,
flat cells are almost invisible due to the limits on both resolution and contrast
