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