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- Natural, uncolored toothpicks
- 2 or 3 small bottle caps
- Wide mouth jar and lid
- 3 or 4 paper cups, or any small containers, which can be discarded after use.
Next, set up your work area.... the kitchen table (make sure to ask a parent for
his or her permis sion), the desk in your room.... any place where you can work
undisturbed.
Label3 of your cups: clean, flush and waste. Fill the flush cup with clean water.
Next, you will obtain a specimen and make your first slide.
Want to See Crystals
Use a measuring cup to measure one or two ounces of hot (but not boiling) water
and pour it into a clean cup. Slowly add as much salt to the water as will dissolve.
Stir the solution continuously while adding the salt.
Use the stirring rod which adding the salt. Remove the sheath from the tip of
needle (make sure you save this and place it back over the needle when you’re
done using it) Use the needle to carefully place one or two drop of the salt
solution onto a clean slide.
Remove the sheath from the tip of the needle make sure the slide to dry. The
slide will dry covered with a white substance. Place the slide into the microscope
stage. Rotate the light source of the microscope until it turns on. Before reading
any further, look through the microscope eyepiece and write down what you
observe.
If you carefully performed the experiment, you will see little crystal cubes. A grain
of table salt is made up of many cubes. Place one or two grains of table salt on
another blank slide and compare it with the slide containing the crystal cubes.
If you wish to save your crystal slides, use a toothpick to put one or two drops of
gum media on the slide and gently place a cover slip on top of the media. (See
image below) Lightly tap the cover slip with a toothpick to evenly spread the
media under the slip.
Attach a label to each slide and set aside for a few days until the media dries. If
you don’t wish to save the slides, wash the slides in clean water and liquid soap.
Rinse well and dry.
Further Experiments
Try out the above procedure with other salts such as Epsom and Rochelle. Sugar
will also crystallize, but you will need to let it dry overnight for the crystals to form.
Preparing a Mount
Dip your spatula in some clean water and make a smear across a clean slide.
Use your tweezers to place a portion of an insect-a wing, a leg, or an antenna-
on the slide. Attach a cover slip over the specimen and place the slide on the
microscope stage.
Obtain a piece of hair from your head or from your pet and place it on a wet slide.
Try this again with more than one type of hair on a slide and compare how they
differ. Also try a piece of fern (or other plant) and pollen and compare them as
well.
To save your slides, put gum media on a clean dry slide and then position your
specimen in the media. Place a cover slip over the media and attach a label.
Creating Smears
Using your scalpel, gently scrape off small shavings from the surface of a freshly
cut potato.
Smear the shavings onto a clean slide. Clean the scalpel by swishing it in fresh
water. Use the needle to put one drop of clean water onto the slide. See image
below). Attach a cover slip to the slide and place to the microscope stage.
Observe the slide and write down your observa tions. You will see hundreds of
starch grains.
Take a few kernels from an uncooked ear of corn. Scrape off some shavings
and make a smear as you did with the potato. Compare how the corn is different
from potato. Create smears of other foods such as apples, bananas, peaches,
and pineapples. You will observe that these items have membranes rather than
starch.
Before you make a permanent mount, you may wish to stain the specimen first.
