EXERCISE 1 MICROSCOPY
BLOOD SMEAR
Procedure:
1. Prepare 3 glass slides. Swab your finger (to be punctuated) with alcohol. Puncture your fingertip with a sterile
lancet.
2. Let a drop of blood fall on one end of the slide. Let the end of the other slide come in contact with the droplet.
Draw the second slide across the first slide at a 30-40 angle to make a thin smear of blood. The smear should cover
about half of the slide. Allow air to dry.
3. Fix the smear by putting 95% ethyl or methyl alcohol on the smear. Let it stand for 3-5 minutes. Let dry.
4. Repeat steps 1-3.
5. Examine one of the blood smears under the low power objective, then switch to the high power objective. Note
you observations.
6. Stain one of the smears following the procedure below.
a) Add a few drops of Wright-Giemsa stain on the smear until it is fully covered ( take note of the stain: specimen
volume ratio). Stain for about 16 minutes, renewing the stain about four times.
b) Rinse the slide with distilled water at room temperature. Drain off the water and leave the slide to dry.
c) Perform steps a) and b) to the other smear using Mayer’s Stain.
7. Examine each slide under the low power and high power objectives. Compare the smears with and without
stains. What are the most notable differences among the three preparations?
WET MOUNTS
Procedure:
1. Gently scrape the inside of your cheek with the blunt end of a toothpick. Bathe the scrapings with a drop of
Ringer’s solution on a glass slide and gently lower a cover slip unto the droplet using forceps and avoiding bubbles.
Remove excess water on or around the cover slip with absorbent paper.
2. Place a drop of aceto-carmine or methylene blue stain at the edge of the cover slip and allow it to diffuse into
the preparation. Let it stand for 3-5 minutes. Observe under low and high power objectives.
3. Obtain a protozoan culture from the hay infusion. Place a drop of the culture on a cavity slide and another on
an ordinary slide.
4. Gently lower a cover slip on each side. Remove excess water. Observe movement of organisms in each
preparation. What other differences can you observe in the two preparations?
5. Gently apply pressure on the cover slip on the ordinary slide. Observe what happens to the specimen.
B. ESTIMATING MAGNIFICATION AND MEASURING MICROSCOPIC OBJECTS
Procedure:
1. Mount a square millimeter of graph paper on a slide under a cover slip. Move the slide such that the paper is on
the center of the field and the two sides of the square are parallel to the edge of the microscope stage.
2. Place a metric ruler on the right edge of your microscope stage so that you can see the ruler with one eye while
you view the slide with the other eye.
3. Keep both eyes open and focus your eyes on both images with the square of graph paper in one eye and the
scale of the ruler in the other eye.
4. When you see the two superimposed images, measure the apparent size of the superimposed millimeter square
as it appears on the ruler. Be sure that you measure from the upper edge of the one line to the upper edge of the
next line to include the thickness of the line in your measurement of the square. Record your measurement.
5. Calculate the magnification under the low power by dividing the apparent size of the millimeter square by its
actual size (1mm). E.g. 100 mm (apparent size)/ 1mm (known size) = 100 X.
6. Using the stained blood smear, determine the size of the red blood cells under the low and high power
objectives.
EXERCISE 2
Procedure:
1. Examine under the high power objective the prepared slide of the bacterium Bacillus sp. Focus on one cell and
draw all the visible structures (Fig. 2.1) Label accordingly and indicate the magnification.
2. Examine under low or high power objective the prepared slide of the protozoan Paramecium sp. Draw and label
structures identified (Fig. 2.2). What are the functions of each structure?
3. Examine the prepared slide of a kidney cross-section. Focus on one cell and identify the visible structures (Fig.
2.3). Label properly.
Compare and contrast the three cells based on the structures visible in each. Indicate which is a eukaryotic and a
prokaryotic cell. Are all single celled individuals considered prokaryotic? Explain. Are all eukaryotes multi-cellular?
Explain.
4. Examine the remaining slides. Draw each cell type studied. Compare the different cell types studied based on
the following characteristics: a) basic shape, b) relative size, c) location of the cell in the body, d) function, and e)
location of nucleus.
PARAMECIUM SP.
OVARY(cross-section)
FROG SKIN(cross-section)
STOMACH(cross-section)
FROG SKIN(cross-seciton)
KIDNEY(cross-section)
TESTIS(cross-section)
Schuch, Raymond, Daniel Nelson & Vincent A.
Fischetti. 2002. A bacteriolytic agent that detects
and kills Bacillus anthracis. Nature, Vol. 418: 884-889
YEAST
University of Texas Medical Branch: Bacillus
University of Wisconsin-Madison: Bacillus
anthracis and anthrax
Paramecium sp
Sources:
Kidney(cross-section) parts
http://legacy.owensboro.kctcs.edu/gcaplan/anat2/h
istology/histo%20e%20urinary%20system.htm
Bacillus sp.
http://microbewiki.kenyon.edu/index.php/Bacillus
Graumann, P. 2007. Bacillus subtilis: Cellular and
Molecular Biology. Caister Academic Press. ISBN 9781-904455-12-7
Innovation in Europe: The decoding of the Bacillus
subtilis genome
Ivanova, Natalia et al. 2003. Genome sequence of
Bacillus cereus and comparative analysis with
Bacillus anthracis. Nature, Vol. 423: 87-91.
Kunst, F. 1997. The complete genome sequence of
the Gram-positive bacterium Bacillus subtilis.
Nature, 390: 249-256.
Read, T. D. et al. 2003. The genome sequence of
Bacillus anthracis Ames and comparison to closely
related bacteria. Nature, Vol. 423: 23-25.
Rosovitz, M. J. & Stephen H. Leppla. 2002. Medicine:
Virus deals anthrax a killer blow. Nature, Vol. 418:
825-826.
Pellicle - a membrane covering that protects the
paramecium like skin
Cilia - hair like appendages that help the
paramecium move food into the oral groove
Oral Groove - collects and directs food into the cell
mouth
Cell Mouth - opening for food
Anal Pore - disposes of waste
Contractile Vacuole - contracts and forces extra
water out of the cell
Radiating Canals - paths to the contractile vacuole
Cytoplasm - intercellular fluid needed to contain
vital cell parts
Trichocyst - used for defense
Gullet - forms food vacuoles
Food Vacuole - storage pocket for food
Macronucleus - larger nucleus which performs
normal cell functions
Micronucleus - smaller nucleus which is responsible
for cell division.
BioMedia. "The Classics of Biology: Paramecium.
Coleman, A.W. "Paramecium aurelia Revisited." The
Journal of Eukaryotic Microbiology.
Fujishima, Masahiro, Miki Kawai, and Ryu
Yamamoto. "Paramecium caudatum acquires heatshock resistance in ciliary movement by infection
with the endonuclear symbiotic bacterium
Holosporaobtusa." FEMS Microbiology Letters 243
Gerritsen, Vivienne Baillie. "The Arsenal
of Paramecium." Protien Spotlight.
Haselton, Aaron. "Paramecium putrinum." The
Connecticut River Homepage.
Kawano T, Kadono T, Kosaka T, Hosoya H. "Green
paramecia as an evolutionary winner of oxidative
symbiosis: a hypothesis and supportive data." Z
Naturforsch (C).
Kimball, John W. Ciliated Protozoans. 14 June 2003.
Samworth, Mike. "Paramecium." Microscopy UK.
1999.
FROG SKIN
http://science.tjc.edu/Course/BIOLOGY/1413/frog
%20skin%20high.jpg
nucleus- at center, hexagonal in shape
TESTIS
Sperling, Linda. Paramecium Genomics. 17 April
2005.
EUKARYOTIC & PROKARYOTIC CELLS
http://grauhall.com/catalog/product_info.php?prod
ucts_id=1057&osCsid=7139a9bc9cf1274711d3c3b0f
36f9327
http://www.diffen.com/difference/Eukaryotic_Cell
_vs_Prokaryotic_Cell
Nucleus- center, small spaces between cells, circular
in shape
Prokaryotes (pro-KAR-ee-ot-es) (from Old Greek probefore + karyon nut or kernel, referring to the cell
nucleus, + suffix -otos, pl. -otes; also spelled
"procaryotes") are organisms without a cell nucleus
(= karyon), or any other membrane-bound
organelles. Most are unicellular, but some
prokaryotes are multicellular).
OVARY
Eukaryotes (IPA: [juːˈkæɹɪɒt]) are organisms whose
cells are organized into complex structures by
internal membranes and a cytoskeleton. The most
characteristic membrane bound structure is the
nucleus. This feature gives them their name, (also
spelled "eucaryote,") which comes from the Greek
ευ, meaning good/true, and κάρυον, meaning nut,
refering to the nucleus. Animals, plants, fungi,
and protists are eukaryotes.
YEAST
SMOOTH MUSCLE
http://www.promocell.com/products/humanprimary-cells/smooth-muscle-cells/
Smooth muscle cells, which form non-striated
muscles, are structurally and functionally different
from skeletal and cardiac muscle cells. They are
located in the walls of blood vessels and hollow
organs like the bladder, the uterus, and the
gastrointestinal tract and are responsible for
involuntary movements like peristaltic contractions,
which propel food along the gastrointestinal tract.
Nucleus- at the middle of strands
http://www.sciencedirect.com/science/article/pii/
S0016648007001062
Nucleus- center, circular in shape, spaces like kidney
cells
http://www.sciencedirect.com/science/article/pii/
S0016648007001062
Nucleus- apparently near the side, semi-oblong in
shape