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ANSWER KEY
Name: __________________________________
Date: ___________________________________
Review Worksheet
FILL IN THE BLANKS
Fill in the blanks with the words or terms which would best complete each sentence.
1. When you carry your microscope to your desk, you should always grasp it using one hand on the
arm
base
_________________
and one arm under the _________________.
2. Once the microscope is set up on our lab bench, plug it in and turn the power on. This will activate the
illuminator
_________________
which will provide the light needed to see your specimen.
stage
stage clips
3. Place your slide on the _________________
and secure it using the two _________________.
The stage
hole
has a _________________
in it which will allow the light through from the light source to the slide. Ensure
lowest
that the stage is positioned at the _________________
height before you start trying to focus.
ocular lens
eyepiece
4. Put one eye against the _________________
, also known as the _________________.
This typically will
body tube
magnify the specimen by ____
which connects to the
10 times. It is placed within the _________________
objective lenses.
nosepiece
low
5. Turn the _________________
to select the _________________
power objective lens. Using this lens,
coarse adjustment knob
slowly scan for the specimen on the slide by turning the ________________________________________
to move the stage closer to the objective lens.
nosepiece
6. Once you locate the specimen, you can get a better resolution by turning the _________________
again to
medium
select the _________________
power objective lens.
high
7. Finally, the _________________
power objective lens can be used to get the most exact focus on the
fine adjustment knob
specimen. To focus using this lens, you should turn the ________________________________________
.
8. The three objective lenses provide different levels of magnification. Typically, the lower power lens
4 times magnification, the medium power lens provides ____
10 times magnification and the
provides ____
40 times magnification. When you go from lower to higher power, the
high power lens provides ____
larger
smaller
magnification gets _________________
but the field of view gets _________________.
9. To adjust the amount of light shining on your specimen, you need to turn the dial on the
diaphragm
_________________.
The dial either opens up the diaphragm which allows more light through, or narrows
the diaphragm, which decreases the amount of light passing through. This is located beneath the
condenser
_________________
lens. This lens helps focus the light from the light source onto the
slide
_________________.
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LABEL THE MICROSCOPE
Identify each part of the microscope and give it the correct label.
ocular lens / eyepiece
body tube
revolving / rotating nosepiece
objective lens
arm
coarse adjustment knob
fine adjustment knob
stage clip
stage
condenser lens
diaphragm
base
illuminator / light source
FIND THE MISTAKE
For each mistake, describe what microscope procedure was incorrectly performed.
10. A student drops the microscope.
The student failed to hold the microscope at the arm and support it at the base at the same time.
11. When first trying to focus, the student sees light but cannot find the specimen on the slide.
The stage was not set to the lowest height so the student has a hard time knowing which direction to
move the stage in order to locate the specimen.
12. A slide gets cracked due to an impact with an objective lens.
The coarse adjustment knob was used with the high power lens. (The coarse knob moved the stage
upwards too quickly, and the student did not have time to assess the distance between the lens and the
slide.)
13. A student is not able to successfully view the specimen because it is too bright.
The student failed to adjust for the brightness using the diaphragm.
14. The student looks into the eyepiece and sees nothing at all but blackness.
The student has not turned on the microscope, or turned it on but failed to plug it in.