1.) Simple Cuboidal epithelium
Lines and forms ducts of many glands
Thyroid gland – 1 follicle, pink blob at center is a colloid, and the cells surrounding the follicle are cuboidal
Red Box= simple cuboidal cells of follicle

Infant Kidney – H&E stain- white space = kidney tubule
Closer look at simple cuboidal cells of the kidney
Simple columnar epithelium

lines much of the human gastrointestinal tract, including the stomach, intestines, gall bladder and the major ducts of the digestive glands (biliary, pancreatic, and salivary)
has oval –shaped nuclei at basal region of cell
Trichome stain – tall columnar epithelium with two goblet cells
4.) Pseudostratified Epithelia
Its name comes from the LM observation that there are multiple layers of nuclei resembling stratified epithelia. However, at the EM level, it is clear that all cells make contact with the basal lamina.
Present in trachea and bronchi
5.) Stratified squamous epithelium-keratinizing
- In thick and thin skin

Thick skin – note the squames on the surface layer = no nuclei in the squamous cells = keratinizing
No nuclei

Skin, Pigmented
There are five layers to the epidermis-stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, stratum basalis
Stratum corneum = outermost layer- very thick in thick skin, also compose the layer of clear or nonnucleated cells, can be 2-20 cells thick
6.) Mucosal stratified squamous layer= non-keratinizing
Found in lip, pharynx, esophagus, vaginal orifice, anus
Cells at surface still have nuclei

7.) Transitional epithelium = uroepithelium
Really is a specialized form of pseudostratified epithelium – because all cells touch the basal membrane
Non-distended bladder epithelium- note the domes covering two or more cells – diagnostic of transitional epithelium transitional epithelium is comprised of three to seven layers of cells with the outer-most layer being cuboidal in shape.

Urinary bladder- distended- note the squamous cells on the surface, might cover two or more cells – diagnostic of transitional epithelium
Epithelium of distended bladder only appears to be two or three cells thick
Muscle of bladder appears thicker in the non-distended form; thinner in the distended form
GLANDS
Either unicellular (goblet cells) or multicellular
Classification of multicellular exocrine glands
1.) Morphology = first part of name = duct branching; second part = shape of secretory structure a.
Secretory structure shape = tubular – can be straight, coiled, or branched, i.
Both types of sweat glands (merocrine sweat glands (small lumen and dark appearing) and apocrine sweat glands(large lumen and light appearing) have their secretory portion in the connective tissue region of this slide.

Axillary skin
Axillary skin- sebaceous gland = acinar gland

Tubuloacinar - The secretory units found in the submandibular salivary glands are a combination of tubes and acini. Recognize that it is difficult to differentiate between tubules and acini without doing serial section reconstruction. Rule of thumb: All salivary glands are compound tubuloalveolar
Submandibular salivary gland= compound tubuloalveolar- meaning the ducts branch
Note that the duct portion of the sweat glands are lined by stratified cuboidal cells (and appear darker), while the secretory portion of the gland is lined by simple cuboidal cells and appear lighter than the ducts.
Note also, the “aprocrine” sweat glands are actually merocrine sweat glands, just like the eccrine glands
(merocrine glands)

Submandibular gland-from Google
Serous glands - The secretory product from these glands is watery in nature. Since the cells are very active in protein synthesis, the cells are darker staining (basophilic) due to abundant rough E.R. and the quick release of their secretory product.
Mucous glands - secretes a mucous, viscous product. Since this product accumulates in the cytoplasm and is then washed out during the preparation of the slide, these cells are lighter stained and appear
"washed-out," and have flattened, basal nuclei.
Sebum glands - The secretory product of these glands is oily in nature. The sebaceous glands are the classic examples of this type. They have a lacy appearance to their cytoplasm due to extraction of the lipid product. As the cells migrate from the periphery where they are produced to the duct they begin to die. Their nuclei become pyknotic and the cell membranes degenerate.
CAN SEE THESE NEAR THE HAIR FOLLICLE IN THE SKIN = BULB SHAPED

Ceruminous glands – they secrete wax and are found in the external auditory canal.
The simple coiled ceruminous glands are located in the deeper dermis more peripheral to the sebaceous glands.
Their appearance is similar to the apocrine sweat glands observed in the axillary skin.
Inspection of these secretory portions at higher magnification reveal blebbing of the luminal surface of the lining cells and, in some places, brownish granules in their cytoplasm which are chacteristic of ceruminous glands.