Epithelial tissue
Epithelial cells
Simple Squamous Epithelium
Stratified Sqaumous Epithelium
Simple Cuboidal Epithelium
Stratified Cuboidal Epithelium
Simple Columnar Epithelium
Pseudostratified Columnar Eptihelium
Locations Cardiovascular System and Lymphatic vessels, visceral & parietal pleura, visceral & parietal pericardium, visceral & parietal peritoneum.
Function Diffusion, Filtration, Secreting Lubricating substances
Microscope Single layered "egg like" cell
Microscope Cilliated and false apperance of multiple layered cells
Locations Upper trachea and upper respiratory tract
Functions Secretes mucus and ciliated tissue moves the mucus
Microscope Single layered ciliated column shaped cells
Location lines bronchi, uterine and uterus, bladder, digestive tract
Functions Absorbs; Secretes mucous and enzymes
Microscope Multiple layered "cube like cells
Location sweat glands, salivary glands and mammary glands
Function Protective tissue
Location in ducts and secretory portions of small glands and in kidney tubules
Stratified Columnar epithelium
Location male urethra and some ducts in glands
Microscope Multiple layered "column shaped" cells
Function Secrets and protects
Function Secrets and absorbs
microscope Single layered "Cube like" cell
Microscope Multiple layered "egg like" cell
Location Lines Mouth, esophagus, and vagina
Function Protects against abrasion
Overview of functions
Covers the body surface and body cavities
Protection
Secretions
Exocrine
protects underlying tissue from Abrasions and foreign bodies
Absorption
Bringing small Molecules into the cell
Diffusion
Movement of molecules against their concentration gradient
Endocrine
Glands made cells that secrete substances on the epithelial surface
Glands that secrete substances into the blood stream
Filtration
Small molecules will be sieved through cell membrane
Sensory
Avascular
Innervated
No viens or arteries present
nerve cells present at the epithelial layer
Special Characteristics
Goblet cell
Microvilli increase surface area and sweep mucus
Golgi apparatus incases mucin in secretory vesicles
looks like a lighter epithelial cell in microscope
Epithelial cell
Apical region
basal region
Cell junction
tight junction holds cells together
gap junction allows ions and small molecules to pass through cells
Desomosome(link the cells like doors to rooms)
basal region sits on basement membrane
The apical region is superficial to the rest of the cell; it is polar; has direct contact with lumen(body cavity)
Transitional epithelium
Look like stratified cuboidal
found in urinary bladder and ureters
Lecture notes
Cilia sweep and microvilli don't sweep (they increase surface area to help with absorbtion
Apical layer of cells will be lighter in color in microscope do to more proteins present at basal layer due to more proteins present
the fact that epithelial cells are so close to one another is defined as cellularity
Histology is the study of tissue; histology is done with a microscope
All epithelial tissue are supported by connective tissue
Regeration
certain epithelial cells are destroyed frequently so they must be able to regenerate.