ZOOL 409
Tuesday and Thursday
Lab Week 6
Primary objective:
Examine skin and recognize its various tissue components.
Slides to examine:

Slide 26, scalp (lots of large hair follicles and
sebaceous glands).

Slide 27, "thick skin" (from palm of hand or sole
of foot); thick epidermis; no hair nor sebaceous
glands. In most boxes, this slide includes
Meissner's corpuscles (in dermal papillae) and
Pacinian corpuscles (deeper in dermis). Also,
elastic fibers are stained on this slide, and
myoepithelial cells are visible in sweat glands.

Slide 28, skin with large apocrine sweat glands
as well as ordinary eccrine sweat glands. This
slide may also include a small site of
inflammation. (Slide 28 in Box 4 does not
include apocrine glands.)
Components to identify:




Layers of epidermis (most distinct in slide 27)
o stratum basale (basal layer / stratum
germinativum)
o stratum spinosum ("prickly cell" layer")
o stratum granulosum (granular layer)
o stratum corneum (cornified layer)
Underlying layers
o papillary layer of dermis (close to epidermis,
includes dermal papillae, with fine-textured
collagen fibers)
o reticular layer of dermis (coarser collagen
fibers)
o hypodermis (subcutaneous adipose)
Cell types
o In epidermis -- keratinocytes , notice cell-cell
junctions (most clearly on slide 27)
o Other, non-keratinocyte cells (melanocytes,
Langerhans cells, Merkel cells)
o In dermis -- see if you can find distinct cell
types (e.g., fibroblasts, macrophages,
lymphocytes, mast cells).
Special structures
o
sweat glands (in slides 26, 27, 28)
o
hair follicles (in slides 26, 28)
o
sebaceous glands (in slides 26, 28)
o
arrector pili muscles (small bundles of smooth
muscle for piloerection, should be present on
slides 26, 28)
o
vasculature
o
Meissner's corpuscles and Pacinian corpuscles
(on slide 27)
o
nerves (deep in dermis, not always noticeable)
Compare / contrast skin with the following
slides. Notice similarities, such as basic tissue
layers. Then look for differences. What features
on these slides are NOT found in skin? And what
features of skin are NOT found on these
specimens?



Slides 35, 36, 37 -- esophagus.
Slides 32 -- tongue.
Slides 76, 77 -- vagina.
_________________________________________
THURSDAY Objective: Catch up on all
tissues covered to date, including skin.
Quiz on reverse side.
Last updated: 21 February 2012 / dgk
Identify the following features on slides from your
study slide set.
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Surface epithelial layers:
____Stratum basale / germinativum)
____Stratum spinosum
____Stratum granulosum
____Stratum corneum
Connective tissue layers:
____Papillary layer of dermis
____Reticular layer of dermis
____Hypodermis (subcutaneous adipose)
Epidermal derivatives
____Hair follicle
____Sebaceous gland
____Sweat gland
____ Duct of sweat gland
____ Secretory segment of sweat gland
Other features:
____Arrector pili (smooth muscle)
____Artery
____Vein
____Capillary
____Nerve