Epithelia Flashcards
Cuboidal cells are _____.
cube-like
The cadherins in _____ link to intermediate filaments.
desmosomes
Epithelial cells directly connect to _____ by attachment of ______ and focal adhesions on the basal surface.
basal laminae; hemidesmosomes
_____ have more than one layer of cells in which cells of the outer layers do not directly contact the basal lamina.
Stratified epithelia
Cancers derived from ________ are known as adenocarcinomas.
glandular epithelium
One side of an epithelium usually has a free outer or _____ surface.
apical
The most common cancers by far are derived from _____, probably because of _____ and their ______.
epithelial tissue; damage exposure; high stem-cell driven turnover rate
_____ contain specific cadherins that link to actin filaments.
Adherence junctions
These promote mechanical strength and resist shearing forces and promote the structural organization of the epithelial sheet.
desmosomes (macula adherens)
Integrins mediate cell-cell linkage by connecting to ____ or _____.
actin; intermediate filaments
Gap junctions promote rapid communication between _____ through diffusion of ___ and small molecules.
epithelial cells; ions
_____ ensure that substances absorbed or secreted must pass through the epithelial cell.
Tight junctions
Beta catenin and protein kinases are examples of ______.
Cadherin-associated proteins
Name 2 cadherin-associated proteins.
Beta catenin and protein kinases
____ are related microtubule extensions that move.
Motile cilia
What is the epithelial to mesenchymal transition?
epithelia forming, disassembling, and reforming in new patterns until body morphology and organ morphogenesis are achieved
The primary function of _____ is to increase surface area.
microvilli
What are cilia?
Microtubule-containing extensions
A tissue that faces blood and lymph is called _____ and is made of _____ cells.
endothelium; endothelial
Stratified epithelia are named according to their ____.
outermost layer
What are microtubule-containing extensions called?
cilia
pemphigus
an autoimmune disease in which antibodies are produced against components of desmosomes in skin, leading to extensive blistering
______ (found around the bladder) are a special case: these epithelia are stratified, but when stretched change their shape from cuboidal to squamous, and appear to decrease the layering.
Transitional epithelia
The primary function of microvilli is to _____.
increase surface area
What is transcytosis?
endocytosis, followed by trans-cellular transport of the vesicle, then exocytosis
Motile cilia tend to be found in epithelia of the _____ and in the _____.
respiratory tract; oviduct
_____ are not motile and appear to function in sensory reception.
Sensory cilia
_____ mediate cell-cell linkage by connecting to actin or intermediate filaments
Integrins
The sheets of cells that line the _____ are called the mesothelium.
enclosed internal spaces of the body cavities
Nutrients and oxygen must diffuse through _____ and through the basal lamina to reach epithelial cells because epi is _____.
connective tissue; avascular
A basal lamina is a thin sheet of _____ that underlies the _____ of each epithelial tissue.
extracellular material; basal surface
_____ must cross the basal surface and basal lamina of the epithelium.
Hormone molecules
Primary cilia is a _____ found on many different epithelial cell types.
single non-motile microtubule-based extension
Transitional epi is comprised of _____ epithelium that is very resilient and _____.
tightly adherent ; stretchable
______ are generally multicellular and secrete materials onto the apical side of epithelial surfaces.
Exocrine glands
Epithelial cell polarity is crucial to allow ________.
unidirectional secretion and/or absorption of molecules
______ are called compound glands.
Multiple branched ducts
A tissue that faces ____ and ____ is called endothelium and is made of endothelial cells.
blood; lymph
______ directly connect to basal laminae by attachment of hemidesmosomes and _____ on the basal surface.
Epithelial cells; focal adhesions
_______ is crucial to allow unidirectional secretion and/or absorption of molecules.
Epithelial cell polarity
Squamous cells are ____.
flattened cells
Epithelial cells are adherent to ______.
one another
______ are a special case where some cells do not reach the free surface (giving a stratified appearance), but all directly rest on the basal lamina.
Pseudostratified epithelia
______ are taller than they are wide.
Columnar cells
What is another name for a tight junction?
zonula occludens
The sheets of cells that line the enclosed internal spaces of the body cavities are called the _______.
mesothelium
ulcerative colitis
extensive ulceration and destruction of the absorptive epithelium
Transitional epithelia (found around the ____) are a special case: these epithelia are _____, but when stretched change their shape from cuboidal to squamous, and appear to decrease the layering.
bladder; stratified
Cancers of epithelial origin are called _______.
carcinomas
Glands secrete their substances by _____ or _____.
total cell disintegration (holocrine); exocytosis
What are stereocilia and where are they found?
long, actin-filled microvilli found in the epididymis and in sensory cells in the ear
______ promote rapid communication between epithelial cells through diffusion of ions and small molecules.
Gap junctions
Endocytosis, followed by trans-cellular transport of the vesicle, then exocytosis, is called?
transcytosis
_____ have all cells arranged in a single layer or sheet.
Simple epithelia
Tight junctions ensure that substances absorbed or secreted must _____.
pass through the epithelial cell
Epithelia cells adhere to and communicate with one another through various _____.
cell junctions
What is the zonula adherens?
the adherence junctions
Mutations in proteins common to cilia or their support structures result in a large set of diseases called _____.
ciliopathies
_____ tend to be found in epithelia of the respiratory tract and in the oviduct.
Motile cilia
Multiple branched ducts are called _________.
compound glands
Key core proteins of tight junctions are _____ and ____.
occludins; claudins
What is the zonula occludens?
a tight junction
What is another name for desmosomes?
macula adherens
Pseudostratified epithelia are a special case where some cells ______ (giving a stratified appearance), but all ______.
directly rest on the basal lamina; do not reach the free surface
______ are transmembrane proteins with extracellular domains that interact with each other and cytoplasmic tails that bind adapters and actin filaments.
Cadherins
_____ secrete materials onto epithelia-lined surfaces or the outside world.
Exocrine glands
______ control various aspects of epithelial polarity, development, and function.
Cadherin-associated proteins
The _____ of the internal passage ways are generally called _____.
moist linings; mucosa
Adherence junctions contain specific _____ that link to _____.
cadherins; actin filaments
Exocrine glands secrete materials onto _____ or _____.
epithelia-lined surfaces or the outside world
Which organs are comprised mostly of epi cells?
liver, pancreas, kidney
_____ secrete substances into the blood stream.
Endocrine glands
Microvilli are _____ that contain ____ connected to cytoskeletal elements in the cell interior.
cell surface extensions; actin bundles
Cadherins are ______ with extracellular domains that interact with ______ and cytoplasmic tails that bind _____.
transmembrane proteins; each other; adapters and actin filaments
The inner surface of an epithelium, called the ____ or _____ surface, is connected to underlying connective tissue.
basal; basolateral
____ organize and promote signal transduction systems.
Primary cilia
Stratified epithelia have ______ in which cells of the outer layers do not _____.
more than one layer of cells; directly contact the basal lamina
Simple epithelia have all cells arranged in ______.
a single layer or sheet
Name an example of a holocrine gland.
sebatious glands
_____ are named according to their outermost layer.
Stratified epithelia
The surface layer of all mucosae is _________.
epithelium
The cadherins in desmosomes link to _____.
intermediate filaments
______ is comprised of tightly adherent epithelium that is very resilient and stretchable.
Transitional epi
A _____ is a thin sheet of extracellular material that underlies the basal surface of each epithelial tissue.
basal lamina
Cadherin-associated proteins control various aspects of _____, _____, and _____.
epithelial polarity, development, and function
Primary cilia organize and promote _____.
signal transduction systems
Name 3 kinds of cilia.
1) primary 2) motile 3) sensory
Endocrine glands secrete substances into the _______.
blood stream
What are 2 other names for endocrine glands?
merocrine or apocrine glands
What is another name for the adherence junctions?
zonula adherens
______ is a single non-motile microtubule-based extension found on many different epithelial cell types.
Primary cilia
What is the macula adherens?
desmosome
What do holocrine glands do?
secrete entire cellular contents
The inner surface of an epithelium, called the basal or basolateral surface, is connected to ______.
underlying connective tissue
Key core proteins of _____ are occludins and claudins.
tight junctions
Columnar cells are _____.
taller than they are wide
Exocrine glands are generally _____ and secrete materials onto the _____ of epithelial surfaces.
multicellular; apical side
______ are flattened cells.
Squamous cells
Cancers of ______ are called carcinomas.
epithelial origin
______ are cube-like.
Cuboidal cells
Cancers derived from glandular epithelium are known as ________.
adenocarcinomas
Hormone molecules must cross the ______ and _____ of the epithelium.
basal surface; basal lamina
_______ are cell surface extensions that contain actin bundles connected to cytoskeletal elements in the cell interior.
Microvilli
Motile cilia are related ____ that move.
microtubule extensions
