Thick Skin

A. Epidermis (stratified squamous kertinizied epithelium)

A1. Stratum corneum 

A2. Rete pegs (interdigitate with dermal papillae)

B. Dermis

B1. Dermal papillae

C. Eccrine sweat gland

C1. Duct (stratefied cuboidal epithelium)

C2. Sweat pore

Thick Skin

C1. Duct (stratified cuboidal epithelium)

C3. Secretory tubule (pseudostratefied epithelium and myoepithelial cells)

Thick Skin

D. Nerve ending - Pacinian corpuscle (pressure receptor)

1st. Bonus Question: What sort of touch is Pacinian corpuscles associated with?

2nd Bonus Question: What is the other corpuscle called? What is it involved with?

3rd Bonus Question: What are Merkel Nerves?

Answers:

Pacinian corpuscles detect pressure and vibrations.

Meissner's corpuscles are involved with light touch. 

Merkel nerve endings are involved with slowly adapting touch receptors. 

Thick Skin

A. Epidermis

B2. Reticular dermis

B3. Duct of sweat gland

C. Hypodermis (contains many fat cells)

C1. Sweat gland

Thick Skin

A1. Stratum Corneum

A2. Stratum lucidum (not labeled, can you find it?)

A3. Stratum granulosum (very basophilic... Why? Keratohyalin granules)

A4. Stratum spinosum (cells attached to adjacent cells with desmosomes)

A5. Stratum Basale

B1. Papillary Dermis (contains Meissner's corpuscle)

Thick Skin

Meisnner's corpuscle, located in the papillary dermis

Thin Skin

A1. Stratum corneum (notice how thin it is)

B. Dermis

C. Eccrine Sweat Gland

D. Hair follicle (notice that there is no hair for thick skin)

E. Sebaceous gland

D3. Epithelial Root Sheath

F. Arrector pili muscle (hint, look for hair follicles nearby)

Thin Skin

C. Eccrine Sweat Gland duct

C1/C2 Secretory component with Myoepithelial Cells (myoepithelial cells will surround the duct)

Thin Skin

E. Sebacious Glands (Holocrine secretion = secretes entire cells that are dead)

D1. Connective tissue root sheath (notice it is pointing right outside the root sheath)

F. Arrector pili muscle (smooth muscle... look for long fusiform shaped cells that are lighter in color. remember smooth muscle nuclei are centered)

Thin Skin

B. Dermis

B1. Duct of Sweat Gland (generally in a line, outlined very dark)

Thin Skin, pigmented

A. Epidermis

A1. Stratum corneum (only a few cells thick)

A2. Stratum basale containing melanin granules*

Notice that a few layers are missing

Lip (lips and the skin bordering it)

A1. Epidermis, stratified squamous keratinized epithelium

A2. Dermis, dense irregular connective tissue (lip has thick elastic bundles)

A3. Hair follicle showing connective tissue papilla

A4. Sebaceous gland (holocrine secretion)

Lip, Thin Skin

A1. Epidermis, stratified keratinized epithelium (flata cells are at the surface but not at the base)

A2. Dermis, dense irregular CT, with thick elastin bundles

Lip, Skeletal muscle support

B1. Multinucleate "cylinders" (separated by tissue shrinkage)

B2. Subsarcolemmal nuclei

Lip, Thin Skin

A4. Sebaceous Gland (holocrine secretion)

A*. Pycnotic nuclei of dying cells

Lip, Oral Mucosa

C2. Lamina Propria (loose to dense irregular connective tissue... notice how ununiformed the texture looks)

C3. Submucosa

*Epithelium -> Lamina propria -> Submucosa

*Epidermis -> Dermis -> Hypodermis

Lips, Oral Mucousa

C1. Epidermis, Stratified Squamous NON-keratinized 

C2. Lamina Propria

[image]

[image]

Lips, Oral mucosa

C3a. Minor Salivary Gland

C3b. Plasma cells between acini of gland

Lip, Thin Skin

B. Vermilion Border (notice the deep connective tissue papillae, the white-ish area)

C1. Mucous Gland, minor salivary gland

D. Orbicularis Oris (skeletal muscle, stains deeper)

Lips 

C1. Mucous Gland, minor salivary gland

Lip, Thin Skin

C2. Mast cell in lamina propria, refer to Page 14 of lab .pdf

Lip, Thin Skin

C3. Plasma cells in stroma of minor salivary gland

Trachea

A. Mucosa

A1. Epitheium (Ciliated pseudostratified columnar with goblet cells)

B. Submucosa (irregular connective tissue)

B1. Mixed serous glands

C. Cartilage rings (C shaped hyaline cartilage)

C1. Perichondrium (peri=middle chondrium=cartilage)

C2. Chondrocytes in lacunae

D. Trachealis Muscle (Smooth Muscle)

E. Adventitia (Irregular connective tissue)

Trachea

Ciliated Pseudostratified Columnar Goblet cells

At the bottom is the basement membrane

Gall Bladder

A2. Lamina Propria loose CT (very vascular = fenestrated capillaries)

A. *Mucosa forms complicated folds that include pockets

B. Mucularis (smooth muscle not in distinct layers, they are in smooth muscle bundles)

C. Adventitia (*dense fibrous CT)

Gall Bladder

Lamina propria

Very vascular and very cellular

Notice the Muscularis, the bundles of smooth muscle.

Gall Bladder

Simple Tall Columnar Epithelium.

Specialized for electrolyte and water absorption.

Vagina, compare and contrast with esophagus and oral mucosa

The Mucosa forms transverse ridges or rugae

A1. Stratified squamous nonkeratinized epithelium

A2. Lamina propria of relatively dense connective tissue with many thin walled veins

Scalp, Hair follicle

A1. Connective tissue root sheath

A2. External Epithelial root sheath

A4. Henle's layer

A5. Huxley's layer

Scalp

B. Sebaceous Gland

C. Arrector pili muscle

D. Sweat Gland

Scalp

A1. Connective Tissue Root Sheath

A2. External epithelial root sheath

A3. Internal Root sheath (containing henle and huxley???)

A6. Hair cuticle and shaft made of hard keratin, cortex and medulla. 

Scalp

A1. Connective Tissue Root Sheath, continuous with the papillary dermis*

A2. External root sheath

A4 Dermal papilla in bulb of hair follicle

A3. Internal Root Sheath

B. Sebaceous gland

C. Arrector Pili Muscle

D. Sweat Gland

Eyelid

A. Stratified Squamous nonkeratinized epithelium

B. Conjunctiva, pseudostratified columnar epithelium with goblet cells

B1. Goblet cells

C. Eyelashes

D. Mebomien sebaceous glands

E. Skeletal muscle

F. Tarsal Plate (dense CT)

G. Lacrimal glands

Active Mammary Gland

A. Lobule

B. Alveolus

C. Interlobular duct

Inactive mammary

A1. Lobule

B. Intralobular CT

C. Interlobular CT

C1. Mast cell (not the same as interlobular duct)