Lab 11 Integumentary System: 1) Index 2) Introduction 3) Things to identify 4) Thick Skin 5) Thick Skin II 6) Thin Skin 7) Pigmented Epithelium 8) Lower Lip 9) Apocrine Sweat Glands 10) Nail Developement 11) Comparisons 12) Practical

 

Thin Skin

 

# 9 - Skin, monkey, 1.5mm, h-e

 

Compare thin skin with thick skin. Observe the reduced layers of the epidermis. Rete ridges are less obvious here. What strata are visible? Note the presence of hair follicles (Ross, p. 385, Fig. 14.13), sebaceous glands, hair shafts, arrector pilorum and eccrine sweat glands. The arrector pilorum is a strap of smooth muscle anchored in the dermis and inserting onto the connective tissue sheath of a hair follicle, causing "goosebumps".

Eccrine sweat glands are simple coiled glands found deep in the dermis. Myoepithelial cells with flattened nuclei may be seen surrounding the cuboidal glandular cells; both cell types lie above the basement membrane. The darker staining straight ducts of the eccrine sweat glands are stratified cuboidal epithelium and lead upwards throught the dermis. In the epidermis the stratified cuboidal duct ends and secretions are released to the surface by means of intercellular channels that twist through the epidermis.

What structures are visible in the hypodermis? Identify the different types of blood vessels there.

References: Gardner, p. 229, Fig.1 - 4 Wheater, p. 167, Fig. 9.15 (eccrine) p. 166, Fig. 9.14 (sebaceous)

 

This is a section of Thin Skin. Can you notice the difference in thickness in the Epidermis in this image (red arrows) than the one from thick skin. There are also a lot of structures in this image. First is the Hair Follicle, indicated by the black arrows. The hair itself is not there because it was lost during slide preperation. Than we have the structures associated with hair follicles. The blue arrows are pointing to Sebaceous Glands. The Green arrow is pointing to the band of smooth muscle called the Arrector Pilorum. These are the srtuctures responsible for making hair "stand on end". `

Red arrows - Epidermis of Thin Skin

Black arrow - Hair Follicle

Green arrow - Arrector Pilli

Blue arrow - Sebaceous Gland

 

 

This is an image of Hair. The blue dotted line is outlining the Bulb of the hair follicle while the red arrow is showing the Shaft of the hair follicle.

 

Red arrow - Hair Follicle Shaft

Blue dotted line - Bulb of Hair Follicle

Thin Skin (hair follicle and sebaceous glands)

 

Hair