Lecture 1 Flashcards
Basolateral Domains
- surfaces of cells locked together by special junctions
- surface in contact with the basal lamina
Apical Domains
-surfaces of cells in contact with lumen or external environment
Epithelial tissues may be derived from…
- Ectoderm
- Endoderm
- Mesoderm
- Epithelial tissues do not contain blood vessels
Ectoderm
-Skin epidermis and glands
Endoderm
-lining of the gastrointestinal tract (including glands)
Mesoderm
-lining of blood vessels, mesothelium, Bowman’s capsule
Basal Lamna
- Next to the epithelial layer, 50-80 nm think
- composed of type IV collagen + glycoproteins
- absent in lymph vessels and hepatic sinusoids
Reticular Lamina
- in contact with underlying connective tissue
- consists of argyrophilic fibers, reticular fibers, and glycoproteins
Basement Membrane
- filtration barrier
- scaffold for embryogenesis and regeneration
- stabilization of tissue shapes
Epithelial Tissues
- line body cavities and cover body surfaces
- form secretory and excretory parts of glands
- may be innervated
Keratin
- protein formed in cells, protective layer
- lightly in esophagus and vagina
- heavily in epidermis
Goblet Cells
-mucus producing cells
Pseudostratified
-simple epithelium, appears stratified, but all cells in contact with basal lamina
Transitional
- simple epithelium
- dome-shaped
- urinary track, erothelium
Apical Surface Modifications
- microvilli (brush border)
- cilia
- stereocilia
Simple Squamous Epithelium
- lines lumina of ducts, vessels, and other tubular structures
- walls of alveoli, Bowman’s, and inner surfaces of membranous labyrinth and tympanic membrane
Simple Cuboidal Epithelium
- may have brush border (kidney tubules) on apical composed of microvilli
- found on surface or ovary, pigmented epithelium of retina, glands and ducts,, terminal bronchioles, choroid plexus, and anterior capsule of lens of eye
Simple Columnar Epithelium
- may have striated border (brush border)
- ciliated found in upper respiratory, uterine tubes, uterus, paranasal sinuses, central canal of spinal cord
- non-ciliated found in digestive beginning with cardia of stomach, gall bladder, parts of excretory ducts
Stratified Squamous Epithelium
- heavily keratinized found in connective tissue papillae and cornea w/o connective tissue papillae
- lightly or non keratinized in esophagus, vagina, lining of mouth, tongue, and epiglottis
Stratified Cuboidal Epithelium
-seldom found, anal mucosa, large excretory ducts of some glands, male urethra
Stratified Columnar Epithelium
-seldom found, ducts of adult sweat glands, fornix of conjuctiva of eye, male reproductive/urinary tract, pharynx, and epiglottis
Pseudostratified Epithelium
- ciliated found in trachea
- w/ sereocilia in epiddymis
- sereocilia simiar to microvilli, but longer and more branched
