ZOOL 409
Lab Week 5
Tuesday (Thursday on back)
TUESDAY Objective: Recognize blood vessels.
Note layers, including:
Practice quiz
intima (very thin, includes endothelium)
The intima is not usually visible, except as nuclei
at the "edge" between vessel wall and lumen.
□
media (usually thickest, with smooth muscle)
The media is always evident for arteries, but
very thin (no muscle) for small veins.
adventitia (surrounding connective tissue.
The adventitia is simply the CT which encircles
and "belongs to" the vessel.

Examine examples of artery and vein.
o
o

Slide 09 -- (H&E stain)
Slide 10 -- (trichrome stain, collagen is blue)
Find as many examples as you can,
of arteries and veins on additional slides.
Recommended:
o
o
o
o

□
Slide 62
Slides 57, 36
Slide 32
Slide 37
Examine cardiac muscle.
o
o
□
Slides 12, 13
Note intercalated discs.
Use your "mind's eye" to imagine the
3-dimensional meshwork of cardiac muscle
cells (rather than individual "fibers").
o Note any visible hints of cardiac stroma,
most especially extensive supply of
capillaries.
□
Vessels in tongue:
____small artery
____larger artery
____small vein
____larger vein
____duct
Vessels in esophagus:
____small artery
____larger artery
____small vein
____larger vein
____duct
Vessels in salivary gland:
____small artery
____larger artery
____small vein
____larger vein
____duct
Vessels in stomach and duodenum:
____small artery
____larger artery
____small vein
____larger vein
Last updated: 13 February 2012 / dgk
ZOOL 409
Thursday (Tuesday on back)
Lab Week 5
THURSDAY Objectives:
2. Recognize the special tissues/organs
which comprise the immune system.
1. Recognize blood cell types on normal
peripheral blood smears
Note large numbers of lymphocytes.
Slide 14 -- normal peripheral blood smear

Note appearance of lymph nodules with
germinal centers.
To sample a smear adequately, systematically
scan an area until you have counted at least 100
white blood cells.

Avoid regions where RBCs are crowded or
clumped together.

Keep a running count of each WBC type.
o
o
o
o
o
o
Neutrophils should be the majority,
60-65 % of the total count.
Lymphocytes should also be fairly common,
20-30 %.
Monocytes are much less common,
roughly 5%.
Eosinophils are rarer still,
1-4 %.
Basophils are quite rare, less than 1 %, and
hard to recognize reliably.
Notice (but do not try to count) platelets, tiny
bits of cytoplasm shed from megakaryocytes.

How does slide 15 differ from slide 14?

How does slide 19 differ from slide 14?
Note distinguishing organizational features such
as capsule, lobes, trabeculae, red and white pulp,
cortex and medulla.

Mucosal lymphoid tissue. Look for lymph
nodules close to surface epithelium.
o
o

Lymph nodes. Look for capsule, cortex with
lymph nodules, medulla.
o


*** NOTE ***
You are also encouraged to examine the
"souvenir" slide you received during our
histotechniques field trip.
Among several other organs (which you should
eventually be able to recognize), this slide includes
a nice specimen of spleen. Some details may show
up better on this slide.
Slides 22, 21
Slide 57 in Boxes 3, 4, 5, 7; and slide 62 in Boxes 5, 7
both include a very tiny lymph node. Can you find it?
Spleen. Look for dense fibrous CT of capsule and
trabeculae; distinguish white pulp (patches
densely packed with lymphocytes, typically with
small arteries in the center) from red pulp
(background texture, with more red blood cells
than in the white pulp).
o
___________________________________
Slide 44 -- Peyer's patches in small intestine.
Slide 25 -- tonsil
Slide 20
Thymus. Notice lobular organization; in each
lobule distinguish cortex and medulla (cells more
densely packed in cortex); notice absence of
lymph nodules.
o
Slides 23, 24
Practice quiz
□
Lymphoid tissue in GI tract:
____lymphocyte accumulation
____lymph nodule / germinal center
Last updated: 29 March 2013 / dgk