Epithelium Cells Flashcards
Epithelial cells fit closely together to
Form continuous sheets
Neighbouring cells are bound by specialized junctions like desmosomes (for strength) and tight junctions (for preventing leakage)
Apical surface
Face outward of the outward body or into a body cavity like the intestines
Helps skin with protection helps intestines absorb with microvilli and respiratory tract movement of mucus with cilia
Basal surface
The basal surface of epithelial tissue is anchored to the basement membrane
The basement membrane acts like glue holding the epithelial tissue in place
It is secreted by both epithelial cells and underlying connective tissue
Avascularity
Epithelial tissue is a vascular no blood supply if it’s own
It depends on diffusion from capillaries in underlying connective tissue for nutrients and oxygen
Regeneration
If we’ll nourished epithelial cells can regenerate easily and rapidly
Simple epithelium
One layer of cells most helpful for secretion,absorption and filtration
Stratified epithelium
More than one layer of cells
Squamous
Flat cells
Cuboidal
Cube shaped cells
Columnar
Tall,collumn shaped cells
Simple squamous epithelium
Single layer resting on basement membrane and ideal for filtration and rapid diffusion and found where gas exchange and nutrient exchange occur
Simple cuboidal epithelialium
One layer of cuboidal cells and is common in glands and small tubes called ducts
Pseudostratifted columnar epithelium
All cells rest on basement membrane
Gives fake appearance that it’s stratified
Functions In absorption and secretion
Lines most of respitory tract
Produce goblet cells that produce mucus to trap dust and debris
Stratified squamous epithelium
Many layers of cells
Provides protection in areas subject to abuse or friction
Stratified cuboidal epithelium
Typically two layers of cells with surface cell being cuboidal
It’s rare and mainly found in the ducts of large glands
