Epithelium Flashcards
(25 cards)
Apical surface
Surface of a cell that faces a lumen or outside area
basolateral surface
Surface of an area that faces away from lumen or outside area
Cornification
Layer of dead cells filled with keratin that forms a
protective barrier over a layer of cells. seen with stratified
Squamous epithelium
Desmosomes
Cell modification that’s responsible for cell-to -cell adhesion
Resistant to shearing forces to the epithelial layer
Endothelium
Type of simple squamous epithelium that lines inside of
Vascular structures
Epithelium
basic tissue type that typically lines a surface (cavity, lumen,or
Outside surface) or forms glands
Hemidesmosomes
Cell modification that’s responsible for cell to extracellular matrix
Keratin
Structural protein intermediate filament that provides a tough protective qualify to some epithelial cell types. See with cornified/keratinized epithelium.
Cilia
An organelle & cell modification that manifests as a
Membrane projection capable of movement
Microvilli
Cell modification that manifests as a membrane projection and increases the surface of a cell
Pseudostratified
Type of columnar epithelium in which the nuclei appear to be arranged in different levels in a cell layer.
Simple
Unaltered arrangement of epithelial cells
Mesothelium
Outer lining of many organs
Stratified
Multilayered arrange went of epithelial aus
Tight Junctions
Cell modification that is responsible for cell to cell adhesion. Transmembrane proteins fused on outer membrane
Gap junctions
Connect cytoplasm of 2 cells
Urotherium
Unique type of epithelium capable of stretching that lines majority of urinary tract
What are the functions of epithelium?
1) protects tissues below it.
2) regulation and exchange of molecules
3) secretion of hormones into blood system and/or secretion of sweat, mucus, etc.
What are the common features between epithelial types?
1) close adiposition of cells
2) free surface of epithelial cells is adjacent to space
3) basal surface is adjacent to connective tissue
4) sheets of epithelial cels man be modified into tubes forming glands.
5) absence of blood vessels within epithelial layer.
What does “basolateral” mean?
Side or bottom of cell
How is epithelium classified in terms of cell layers?
Simple (<1), stratified (2 or more)
What are the differences between glandular and non-glandular epithelium?
Glandular is invagination/aggregation of epithelium that forms solidtissue structure with endocrine or exocrine function
Non-glandular has lining function that controls movement materials in and out.
What are some cell modifications of epithelial cells and their functions?
Microvilli - increase cell surface
Cilia - aid in movement
Cell connections - aid in cell communication
What is the difference between a desmosome and a hemidesmosome?
A desmosome attaches to microfilaments of cytoskeleton made of keratin protein - connects cells
Hemidesmosomes attach the epithelial cell to basement membrane instead of adjacent cell
