BIOD 171 Microbiology Module 3 Exam
Questions and Answers
1. True or False: A nanometeris longer than a micrometer.: False. A nanometer is
1,000 times smaller than a micrometer.
2. What is the total magnification (relative to your eye) of a sample imaged
with a 60x objective and a 10x eyepiece? Show your math.: 60 x 10 = 600x
magnification
3. Assuming a fixed ocular, identify the part of the microscope you would
adjust to enhance the magnification of a sample.
A. Objective
B. Condenser
C. Iris diaphragm
D. Eye piece: A. Only the oculars (eyepiece) and the objectives contribute to the magnification of the
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, sample.
Since the eyepiece is fixed, only the objectives could be altered.
4. What is the total magnification (relative to your eye) of a sample imaged
with a 20x objective and a 15x eyepiece? Show your math.: 20 x 15 = 300x
magnification
5. True or False: Staining is often required to image a cell that is adherent
and flat (thin).: 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 the sample.
6. 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.
Select all that apply.
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6
Questions and Answers
1. True or False: A nanometeris longer than a micrometer.: False. A nanometer is
1,000 times smaller than a micrometer.
2. What is the total magnification (relative to your eye) of a sample imaged
with a 60x objective and a 10x eyepiece? Show your math.: 60 x 10 = 600x
magnification
3. Assuming a fixed ocular, identify the part of the microscope you would
adjust to enhance the magnification of a sample.
A. Objective
B. Condenser
C. Iris diaphragm
D. Eye piece: A. Only the oculars (eyepiece) and the objectives contribute to the magnification of the
1/
6
, sample.
Since the eyepiece is fixed, only the objectives could be altered.
4. What is the total magnification (relative to your eye) of a sample imaged
with a 20x objective and a 15x eyepiece? Show your math.: 20 x 15 = 300x
magnification
5. True or False: Staining is often required to image a cell that is adherent
and flat (thin).: 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 the sample.
6. 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.
Select all that apply.
2/
6
