BIOD 171: MODULE 3 QUESTIONS AND
ANSWERS WITH COMPLETE
SOLUTIONS 100% CORRECT RATED A+
||UPDATED 2025
The microscope is perhaps the most:
✔✔Important resource for studying biology at the microscopic level.
Micrometer
✔✔A micrometer (µm) is one-millionth of a meter, equal to 10−610^{-6}10−6
meters.
Nanometer
✔✔A nanometer (nm) is one-billionth of a meter, equal to 10−910^{-9}10−9
meters.
Two critical factors influence our ability to see an object:
✔✔Resolution and contrast
Resolution
✔✔The ability to distinguish two objects as separate when they are close together.
✔✔The smaller the distance between two objects, the higher the resolution needed
to see them as distinct.
Contrast
✔✔The difference in light absorption between an object and its background.
✔✔Low contrast makes objects harder to see; higher contrast makes them easier to
visualize.
, Brightfield microscopes - ANSWER✔✔are the simplest form of light, or optical,
microscopes.
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: - ANSWER✔✔it first passes through a
condenser converging the light beams into a focused area on the sample.
The Iris Diaphragm - ANSWER✔✔controls the amount of light that passes
through the sample and into the objective lens.
Objective Lens - ANSWER✔✔is the lens closest to the sample and yields the
greatest amount of magnification.
(Note: The degree of magnification is directly proportional to the amount of light
needed. Thus, to image samples clearly at higher magnifications, more light is
required).
Once light passes through the sample and the objective lens: - ANSWER✔✔it is
directed through the ocular lens, or eyepiece, to your eye.
the most common power of an ocular lens is 10x.
for a microscope using two lenses (objective and ocular) the total magnification of
a specimen is multiplicative.
ANSWERS WITH COMPLETE
SOLUTIONS 100% CORRECT RATED A+
||UPDATED 2025
The microscope is perhaps the most:
✔✔Important resource for studying biology at the microscopic level.
Micrometer
✔✔A micrometer (µm) is one-millionth of a meter, equal to 10−610^{-6}10−6
meters.
Nanometer
✔✔A nanometer (nm) is one-billionth of a meter, equal to 10−910^{-9}10−9
meters.
Two critical factors influence our ability to see an object:
✔✔Resolution and contrast
Resolution
✔✔The ability to distinguish two objects as separate when they are close together.
✔✔The smaller the distance between two objects, the higher the resolution needed
to see them as distinct.
Contrast
✔✔The difference in light absorption between an object and its background.
✔✔Low contrast makes objects harder to see; higher contrast makes them easier to
visualize.
, Brightfield microscopes - ANSWER✔✔are the simplest form of light, or optical,
microscopes.
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: - ANSWER✔✔it first passes through a
condenser converging the light beams into a focused area on the sample.
The Iris Diaphragm - ANSWER✔✔controls the amount of light that passes
through the sample and into the objective lens.
Objective Lens - ANSWER✔✔is the lens closest to the sample and yields the
greatest amount of magnification.
(Note: The degree of magnification is directly proportional to the amount of light
needed. Thus, to image samples clearly at higher magnifications, more light is
required).
Once light passes through the sample and the objective lens: - ANSWER✔✔it is
directed through the ocular lens, or eyepiece, to your eye.
the most common power of an ocular lens is 10x.
for a microscope using two lenses (objective and ocular) the total magnification of
a specimen is multiplicative.
