epithelial tissue Flashcards
shapes of epithelial cells
squamous, cuboidal, columnar
functions of epithelial cells
physical protection
control permeability
provide sensation
produce specialised sercretions
name 3 intercellular junctions
gap
tight
desmosomes
what attaches the deepest epithelial cells to the basal lamina?
Hemidesmosomes
describe the structure of simple squamous
one layer
scrambles eggs
delicate
where is simple squamous usually found and why?
in protected regions in the body, where absorption or diffusion takes place, needs slick/slippery surfaces to reduce friction.
kidneys, inside the eye, at the gas exchange surfaces of the lung
what type of epithelium lines each venteral body cavity?
mesothelium (simple squamous)
what type of epithelium lines the heart and blood vessels?
endothelium
where is stratified squamous found and why?
in places of severe mechanical or chemical stresses(multi layers)
mouth, throat, esophagus, rectum, anus and vagina
what is keratin, where is it found and what does it do?
chemical that is found in stratified squamous cornified(or keratinised) epithelium it makes our skin water proof, and tough does not need to stay hydrated
dead skin cells
what type of epithelial tissue is found in the bladder?
transition
what is the respiratory epithelial?
pseudostratified
describe the structure of pseudostratified epithelium
simple columnar ciliated
Exocrine glands
Secrete onto external surfaces or into internal pathways(ducts) that then connect to exterior
Endocrine glands
Secret hormones or precursors into the interstitial fluid, then usually distributed by blood steam
What type of epithelium lines the intestine?
Simple columnar epithelia
What type of epithelium lines the salivary gland duct?
Stratified columnar epithelium
What is the use of glandular epithelia?
Specialised sercretions
What type of epithelium lines the trachea
Ciliated Pseudostratified columnar
What type of epithelium lines the small intestine?
Simple columnar..micro villi
Allows absorption
What are 2 special names given to simple squamous epithelia and where are they found
Mesothelium - ventral body cavities
Endothelium - lines heart and blood vessels
What lines all ventral body cavities
Mesothelium - simple squamous
What lines the heart and blood vessels
Endothelium - simple squamous
Where is simple cuboidal epithelium found?
Lining exocrine glands and ducts, portions of the kidneys and lining secretory chambers in the thyroid gland
Where is stratified cuboidal found?
Rare
Found along ducts of sweat glands and mammary glands and other exocrine glands
What is the term meaning no blood vessels?
Avscular
