Epithelial Tissue III (exam 1) Flashcards
what are microvilli supported by
Cross-linked actin bundles
Are microvilli motile
No
Microvilli tend to form what cross the apical membrane
Brush border
What is microvilli primary function
to increase the surface are of absorption
Where are microvilli typically found
on the intestinal epithelium and on parts of renal tubules
what is the microvilli core composed of
Actin filament which extends into the terminal web
What is the terminal web
A network of cytoskeletal proteins (such as keratins) under the apical membrane of the cell
The distal end of the actin filament core in microvilli is capped by _______ and what is the caps function
Formin
Formin interacts with the barbed ends of the actin filaments
Formin regulates the assembly of the actin filaments at the barbed ends
The actin filaments that make up the core of the microvilli are cross-linked by what
Villain and fimbrin
what is the structure of a cilium
9 peripheral doublets with a central pair of microtubules
- each doublet consists of alpha tubule and beta tubule
Describe the structure of the alpha tubule in each of the 9 peripheral doublets of a Cilium
13 protofilaments
Radial spokes extending to sheath around central pair
Pair of dyne arms projecting to beta unit of next doublet
Describe the structure of a beta tubule in each of the 9 peripheral doublets of a Cilium
10-11 protofilaments
What do cilia develop from
Basal bodies