Epithelium Flashcards
Tight junctions
prevent paracellular passage (Tight junctions = zonula occludens) 2. Proteins of tight junctions - claudin and occludin, zonula proteins)
3. Cytoskeletal component: Actin
Cilia
i.e Cilia are composed of microtubules in a 9+2 axoneme and using motor proteins they are able to whip back and forth to move a cell or ECM materials.
Sterocilia
Stereocilia (actin) - ear and reproductive tract
Basal lamina
closest to basal side of epithelium; contains:
- Laminin –
- Type IV Collagen polymer
- Synthesized by the epithelial cells
Reticular lamina
Type III collagen
Endocrine glands
Endocrine have capillary beds!! Endocrine glands lose ducts and associate with capillaries
Exocrine glands
Exocrine have ducts!! Duct connects acini to surface above
Merocrine secretion
common method of protein or glycoprotein secretion. involve exocytosis from membrane bound vesicles . serous or mucous according to the nature of the products. mucous cells like goblet cells have a RER and golgi complexes filled with secretory
Holocrine secretion
cells accumulate product continually and release product into the lumen- sebaceous glands of the skin
Apocrine secretion
product accumulates at apical end, portion is then pinched off by a small amount of cytoplasm and cell membrane.
Simple tubular
mucous glands of colon
branched tubular
glands in uterus and stomach
coiled tubular
sweat glands
acinar or aleolar
small mucous glands along urethra
branched acinar
sebecous glands of the skin
