Need Help? Toll Free 866-252-3811
6 b) using a suitable media programmer.
4. Viewed Object – condition and preparation
4.1Condition
Transparent and non-transparent specimens can be examined with this
microscope, which is a direct as well as transmitted light model. If
opaque specimens are examined - such as small animals, plant parts, tis-
sue, stone and
so on - the light is reflected from the specimen through the lens and eye
-
piece, where it is magnified, to the eye (reflected light principle, switch
position I). If opaque specimens are examined the light from below goes
through the specimen, lens and eyepiece to the eye and is magnified en
route (direct light principle, switch position II). Many small organisms of
the water, plant parts and finest animal components have now from nature
these transparent characteristic, other ones must be accordingly prepared.
Is it that we make it by means of a pre-treatment or penetration with suit-
able materials (media) transparent or thus that we cut finest wafers off of
them (hand cut, Microtom) and these then examine. With these methods
will us the following part make familiar.
manufacturer of thin preparation cuts
Specimens should be sliced as thin as possible, as stated before. A little
wax
or paraffin is needed to achieve the best results. A candle can be used
for the purpose. The wax is put in a bowl and heated over a flame. The
specimen is
then dipped several times in the liquid wax. The wax is finally allowed to
harden.
Use a MicroCut (Fig 5.36) or knife/scalpel (carefully) to make very thin
slices of the object in its wax casing. These slices are then laid on a glass
slide and
covered with another.
manufacturer of an own preparation
Put the object which shall be observed on a glass slide and give with a
pipette (Fig. 5.34 B) a drop of distilled water on the object (Fig. 6).
Set a cover glass (in each well sorted hobby shop available) perpendicu-
larly at the edge of the water drop, so that the water runs along the cover
glass edge (Fig. 7). Lower now the cover glass slowly over the water
drop.
Note:
The gum medium supplied (Fig 5.37 B) is used to make permanent slide
cultures. Add it instead of distilled water. The gum medium hardens so
that the specimen is permanently affixed to its slide.
5. Experiments
If you made yourself familiar with the microscope already, you can ac-
complish the following experiments and observe the results under your
microscope.
5.1 Newspaper print
Objects:
1. A small piece of paper from a newspaper with parts of a picture and
some
letters
2. A similar piece of paper from an illustrated magazine
Use your microscope at the lowest magnification and use the preparation
of the daily paper. The letters seen are broken out, because the news-
paper is printed on raw, inferior paper. Letters of the magazines appear
smoother and more complete. The picture of the daily paper consists
of many small points, which appear somewhat dirty. The pixels (raster
points) of the magazine appear sharply.
5.2 Textile fibers
Items and accessories:
1. Threads of different textiles: Cotton, line, wool, silk, Celanese, nylon
etc..
2. Two needles
Each thread is put on a glass slide and frayed with the help of the two
needles. The threads are dampened and covered with a cover glass. The
microscope is adjusted to a low magnification. Cotton staples are of
vegetable origin and look under the microscope like a flat, turned volume.
The fibers are thicker and rounder at the edges than in the center. Cotton
staples consist primary of long, collapsed tubes. Linen fibers are also
vegetable origin; they are round and run in straight lines direction. The
fibers shine like silk and exhibit countless swelling at the fiber pipe. Silk
is animal origin and consists of solid fibers of smaller diameter contrary
to the hollow vegetable fibers. Each fiber is smooth and even moderate
and has the appearance of a small glass rod. Wool fibers are also animal
origin; the surface consists of overlapping cases, which appear broken
and wavy. If it is possible, compare wool fibers of different weaving
mills. Consider thereby the different appearance of the fibers. Experts can
determine from it the country of origin of wool. Celanese is like already
the name says, artificially manufactured by a long chemical process. All
fibers show hard, dark lines on the smooth, shining surface. The fibers
ripple themselves/ crinkle after drying in the same condition. Observe the
thing in common and
differences.
5.3Salt water prawns
Accessories:
1. Prawn eggs (Fig 5.37 D)
2. Sea salt (Fig 5.37 C)
3. Prawn breeding plant (Fig 5.35)
4. Yeast (Fig 5.37 A)
5.3.1The lifecycle of the saltwater prawn
The saltwater prawn or artimia salina to scientists has an unusual and
interesting
lifecycle. The female’s eggs are hatched without any male shrimp having
to fertilize them. The resultant baby prawns are all female. Under unusual
circumstances such
as when a swamp is drained the eggs may produce male prawns. These
males fertilize the female’s eggs, resulting in a specific type of eggs.
These are called winter eggs and have a thick shell as protection. They’re
pretty rugged and can survive the swamp or lake drying out causing the
death of the entire prawn population for up to a decade in a form of hi-
bernation. The eggs hatch once the right ambient conditions again obtain.
The eggs supplied (Fig 5.37 D) are of this type.
5.3.2 Hatching of the salt water prawn
To hatch the prawn it is essential to first have a saline solution suited to
the prawn’s needs. Fill half a liter of rain- or fresh-water in a container.
Let it stand for about thirty hours. As water evaporates over time it’s
a good idea to have a second container of such water left standing for
thirty-six hours. Once it’s stood for this length of time pour half of the sea
salt supplied into one of the containers (Fig 5.37 C)
and stir until it has dissolved. Then pour some of it into the prawn breed-
ing plant (Fig 5.35). Add a few eggs and close the lid. Put it somewhere
with plenty of light but not in the direct sun. The temperature should be
approximately 25 C. The prawns will hatch in two or three days at this
temperature. Should any water evaporate during this time replace it from
the second container.
5.3.3 The saltwater prawn under the microscope
What comes out of the egg is known as a nauplius larva. Use the pipette
(Fig 5.34 B) to put some of them on a slide for examination. They will
move in the solution using their hair like limbs. Remove a few daily from
the container for examination under the microscope. If you do so and
save the pictures made with the MicrOcular you will then have a seam-
less record of the prawn’s lifecycle. You can remove the upper lid of the
prawn bleeding plant and put the whole thing under the microscope. The
larvae will mature in six to ten weeks depending on ambient temperature.
You will soon have bred an entire generation of saltwater prawns that
constantly reproduce.
