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Microscopy worksheet

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Applied Science Microscopy
Objective: To become familiar with the functions of the video-microscope and the preparation and
use of wet mount slides.
Materials:
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Glass slides
Cover slips
Water and pipette
Newspaper
Scissors
Procedure:
1) Find and cut out a lower case “e” from the newspaper.
2) Prepare a wet mount slide of the letter “e”.
A wet mount slide will allow you to observe the preserved or live material under the microscope.
Follow the instructions below to prepare a wet mount slide for the specimen you wish to observe:
 Using a pipette or dropper bottle, place a drop or two of water on a clean, dry slide. (Note
that if the specimen you wish to observe is in a liquid environment, this step is
unnecessary.)
 Place the specimen in the drop of water.
 Place a cover slip over the water and your specimen by holding the cover slip at a 45degree angle and slowly lowering the cover slip on to the specimen. This ensures no air
bubbles form under the cover slip.
3) Ensure that the rotating nose piece is set to the low power objective lens - x4. Place the slide
with the “e” on the stage of the microscope. The “e” should be in an upright position and situated
directly under the low power objective lens.
4) Looking through the eyepiece of the microscope or on the screen, slowly turn the coarse
adjustment knob until the “e” comes into focus. (Caution: When using the adjustment knobs
always check the space between the stage and the objective lens: NEVER let the lens contact the
slide or stage)
Q1) Describe the appearance of the “e” as viewed under the low power objective lens in comparison
to the appearance of the “e” with the naked eye.
5) Now, while observing the “e” through the eyepiece, use the stage control knobs to move the slide
towards you and then to the left.
Q2) In what direction does the “e” appear to move when you move it towards you? When you move
it to the left?
6) Carefully rotate the nosepiece so that the medium power objective lens - x10 is above the “e”.
Using the fine adjustment knob, bring the “e” into focus.
Q3) Describe the appearance of the “e” as viewed under the medium power objective lens in
comparison to the “e” viewed under low power objective lens.
Q4) Do you see more or less of the “e” now than when you observed it on a lower power?
7) Prepare a wet mount slide of pond water
 Using a pipette or dropper bottle, place a drop or two of pond water on a clean, dry slide.
 Place a cover slip over the water and your specimen by holding the cover slip at a 45degree angle and slowly lowering the cover slip on to the specimen. This ensures no air
bubbles form under the cover slip.
 Follow steps 3 – 4 above and see what you can see
8) Observation of Your Own Hair
 Get a clean glass slide.
 Wipe a thin layer of nail polish on the slide the length and width of a cover slip.
 Either pull out or cut a hair from your head.
 Slowly lower the hair into the nail polish being careful not to move it about
 Wait 10 minutes to remove the hair.
 Observe the slide and sketch your cuticle
Finally, remove the slide and set it aside. Rotate the nosepiece to the low power objective lens.
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