EPITHELIUM Flashcards
Is the epithelium vascular or avascular?
avascular
epithelia rest on the ? membrane which separates it from the other tissue
basement membrane
Where can you find membranous epithelium?
covering external surfaces, lining internal closed cavities, as well as lining body tubes which communicate with the exterior
What are the 2 types of epithelium?
- Membranous
- Glandular epithelium
What are the 2 types of glandular epithelium?
- exocrine glands
- endocrine glands
How can you determine if a gland is exocrine or endocrine?
excocrine glands have a duct. endocrine glands lack a duct
What are the 3 distinct structural domains of epithelial tissue?
- apical surface
- lateral domain
- basal surface
Where is the basal surface located?
Anchored to the basement membrane
What are the main features of the lateral domain?
presence of tight junctions just below the apical surface
gap junctions above the basal surface
What is the function of tight junctions?
prevent free movement of molecules across epithelial sheets
What is the function of gap junctions?
allowing various molecules and ions to pass between cells.
allows the sharing of substances between cells.
What types of specialization can be present in the apical domain?
microvilli, cilia
define microvilli
what is the function?
hair-like projections on the surface of epithelial cells
fxn: increase SA, increase absorption of nutrients into epithelial cells
define cilia
what is an example of a function?
motile projections of some epithelial cells
fxn ex: sweep mucus and germs out of the lungs
What type of epithelia?
keratinized stratified squamous epithelium
Identify the structure idicated by A
Identify the epithelium indictaed by B
A. Keratin
B. Keratinized stratified squamous epithelium