Epithelial Tissue Flashcards
a layer of cells that cover a surface
epithelia
Functions of epithelia
- covering and lining a surface (skin) - barrier
- regulation of materials and sensory information (absorption, secretion, sensation, lubrication)
- contractility ( sweat and mammary glands)
- protection from external environment
epithelia cell that is flat, very thin in cross section
squamous
epithelia that appear square in cross section
cuboidal
epithelia that appear rectangular, tall, long in cross section
columnar
in reality, the cells are really ______ in 3D
polyhedral
epithelia consisting of one layer of cells
simple
location of simple squamous
air sac of lungs, blood vessels
location of simple cuboidal
kidney tubules
location of simple columnar
small intestine- jejunum
epithelia consisting of more than one layer of cells
stratified
location of keratinized stratified squamous epithelium
skin
location of non keratinized stratified squamous epithelium
mouth, vagina
location of stratified columnar epithelium
rare- male urethra
location of stratified cuboidal epithelium
rare- sweat glands
location of transitional epithelium
bladder
location of pseudo stratified epithelium
respiratory tract, trachea
found wherever an epithelium contacts connective tissue, consists of granular layer of thin fibrils that is composed of collagen, glycoprotein called proteoglycans
basal lamina
basal lamina consists of three parts
- lamina densa
- lamina rara
- lamina reticularis
a fibrous , darkly staining layer into which fibers from hemidesmosomes, as well as adjacent extracellular matrix, insert
- part of basal lamina
lamina densa
the lamina densa is composed of type ___ collagen and _______
type IV
proteoglycans
a clear non staining layer ( may be on one or both sides of the lamina densa )
- part of basal lamina
- contains glycoprotein and laminin
lamina rara
part of the basal lamina that is between the lamina dense and lamina rara and underlying tissue. Meshwork of reticular fibers
lamina reticularis
like sticks to like
cohesion
epithelia cells cohere to each other . in part due to binding action of surface molecules such as _________
glycoproteins
______ is important in cohesion, and cells tend to disassociate with out it
calcium
disk shaped structures on cells that foam adjacent electron dense areas seen in ultrastructural preps.
desmosomes (macula adherens)
_____ ______ restricts direct passage of solids and fluids from outside of epithelia into regions between the epithelial cells
zonula occludens
acts as anchoring point for terminal web of apical actin filaments found in tall columnar epithelial cells
zonula adherens
autoimmune disease caused by antibodies damaging the desmoglein proteins in the maculae adherens (desmosomes)
pemphigus folaceus
glands where secretion released into surrounding capillaries, no ducts.
endocrine
glands where secretion usually released through dicts. secretory cells form a true epithelium
exocrine
the change in the type of adult cells in a tissue to a form abnormal for that tissue
metaplasia
smoking causes metaplasia where columnar turns into
squamous
metaplasia where transitional turns into ____ due to a bladder stone
squamous
type of exocrine secretion
product released by exocytosis from cell cytoplasm
merocrine
type of exocrine secretion
whole cell is shed as secretion, sebaceous glands of skin
holocrine
type of exocrine secretion
apical portion of cell is shed as secretion, like mammary gland, goblet cells
apocrine
exocrine gland with no duct , individual secretory cells embedded in an epithelium that lines a structure (goblet cells )
unicellular gland
gland that has a single, non branched duct
- the secretary components can be branched
simple gland
type of exocrine gland where the duct is branched, ramified
compound
type of exocrine gland where the secretory parts consist of tubes
tubular glands
type of exocrine gland where the secretary portion consists of a coiled tube
coiled gland
type of exocrine gland where the secretory part consist of bag like structures
acinar or alveolar gland
type of exocrine gland where secretory parts consist of a combination of bags and tubes
tubuloacinar gland or
tubuloalveolar gland
T/F: there are blood vessels in epithelium
false
