A fried egg
The cheek epithelial cells are flat and irregularly shaped. They are polygonal squamous cells that have a very thin membrane.
Stratified Squamous Epithelium
1. squamous (flattened) 2. cuboidal (cube-shaped) 3. columnar
Epithelial tissue is a major category of tissue which lines all our body surfaces. It can be classified by a combination of shape (squamous, cuboidal, columnar) and layers (simple, stratified, pseudostratified).
On what bases are epithelial tissues classified?
The cheek epithelial cells are flat and irregularly shaped. They are polygonal squamous cells that have a very thin membrane.
Stratified Squamous Epithelium
1. squamous (flattened) 2. cuboidal (cube-shaped) 3. columnar
Epithelial tissue is a major category of tissue which lines all our body surfaces. It can be classified by a combination of shape (squamous, cuboidal, columnar) and layers (simple, stratified, pseudostratified).
On what bases are epithelial tissues classified?
The inner vaginal wall is lined by stratified squamous epithelial cells. These cells are layered and flat in shape, which helps protect the vaginal wall from friction and damage.
Epithelial cells of the Pulmonary surface, + epithelial duct elements of Glands, Ciliary epithelium, esophageal, germinal {of Ovaries}, glandular and membranous: Cornea, larynx, nasopharynx, small intestine, stomach, olfactory, pigments of the Retina. As well, here are the rest: Pseudostratified, seminiferous, simple, simple columnar, simple cubical, simple cuboidal, simple squamous, stratified, stratified columnar, stratified cuboidal, stratified squamous, surface - of stomach - , and transitional.
Cells can be any shape and it is normal for them to be irregular. In my studies, i have never come across a perfectly shaped cell.
columnar shape
Well, there lots of shapes, but three common forms are cuboidal shaped cells (which are like cubes), squamous cells (which are like cuboidal except flattened), and then there are columnar cells (which are shaped like columns).As for the flattened cells that are important for protection, this is clearly referring to squamous epithelial cells. Every lumen of our bodies has a layer of epithelium surrounding it, partly for protection. The cells of these layers can be a variety of shapes, but squamous is common. Skin, for example, is squamous epithelial tissue. And yes, these cells fit together like tiles, so their shape is very important to the barrier function they serve. Epithelial cells can form different kinds of junctions between each other. One type, called a 'tight junction', causes the cells to bind to each other extremely closely.
They are generally classified by size and shapeEpithelial tissue is classified according to:1. The number of cell layersSimplePseudostratifiedStratified2. The shape of the cellsSquamousCuboidalColumnarMixed/Varied3. Whether the cells are ciliated or unciliatedSo examples of epithelial tissue using this classification would beSimple squamous (found in the lungs and kidneys)Simple cuboidal (found in the lining of the stomach and fallopian tubes)Ciliated pseudostratified columnar (found lining the nasal cavity)
endocrine (where the secretions are put directly into the bloodstream) or exocrine (where the secretions are carried to the epithelial surfaces)