Truckee Meadows Community College | BIOL 190L
d. How do the two wetmounts differ?
e. What cell structure(s) can you identify with the stain?
Waste Disposal. When finished, dispose of the Elodea leaf and cheek cell wetmounts in the
container filled with blue disinfecting solution at the front lab bench.
5. Blood Cell Pathologies. Medical diagnoses can be made by comparing the histology, or microscopic study of tissue, in the healthy and diseased states. In this exercise, you will examine a
smear of normal human blood and compare it to smears of blood with disorders. (The blood
used in this exercise has been fixed and thus poses no threat of transmitting infectious agents.)
a. Blood is made up of red blood cells (erythrocytes) and white blood cells (leukocytes), cell
parts called platelets, and liquid plasma. Examine the smear of normal blood. There are 5
types of leukocytes: Monocyte, Eosinophil, Lymphocytes, Neutrophils, and Basophils You
will need to look at the sample under at least 400X total magnification—1000X (and oil
immersion) is best.
The Elements of Blood
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Chapter 4 | Basics of the Optical Microscope
This is a great opportunity to practice viewing samples at 1000X using oil immersion.
b. Look at the chart of blood cells on the wall. Identify the cells can you see in your slide.
Describe what these cells look like. Note the cell shape and color in particular. Also try to
classify any white blood cells you observe.
c. Next, examine the iron deficiency and sickle cell anemia blood smears and compare them to
the normal blood sample. Are there differences found in shape and size of the erythrocytes?
Is there a greater density of erythrocytes in one or the other specimen? Are there observable
differences in the central pallor (center) of the erythrocytes?
Remember that this technique is actually used to help diagnose blood disorders. Make careful observations.
d. Reexamine the normal blood smear at 400X. This time count the number of white blood
cells that you see in three independent fields and record this data in the following table.
e. Next, examine the acute myeloblastic leukemia slide. Acute myeloblastic leukemia is a cancer
of the white blood-forming bone marrow cells, and is characterized by the presence of many
myeloblasts, or immature white blood cells. Count the number of white blood cells that you
see in three independent fields, and record this in the following data table.
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Truckee Meadows Community College | BIOL 190L
BLOOD
SAMPLE
FIELD 1
FIELD 2
FIELD 3
AVERAGE #
OF WHITE
CELLS PER
FIELD
Normal
Acute Myeloblastic
Leukemia
f.
Calculate the average number of white cells per field of view at 400X and record it in the
data table. Was there a mathematical difference in the averages?
Now calculate the standard deviation and p-value (using a Student's t-test) between
normal & acute myeloblastic leukemia blood samples. Was the difference in # of
white blood cells between groups statistically significant?
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