Epithelium Flashcards
All the organs of your body are composed of 4 tissues…..which are?
epithelium, muscle, nerve and connective
epithelia are sheets of cells that ____ or _____ internal and external body surfaces
line, cover
the functions of the epithelium include ________, ________ and _______
protection, absorption, secretion
The epithelia is attached to underlying ____________ by an acellular basement membrane where the basement membrane is a meshwork of _____ and ______
connective tissue, carbohydrates, proteins
the connective tissue underneath the epithelium is called the
lamina propria
epithelial cells lack _______, they derive nutrients and oxygen from vessels in the _______
blood vessels, lamina propria
epithelia are classified into 3 shapes that include
squamous, cuboidal, and columnar
epithelial cells can be arranged into either a ______, _________, or ________ layer
simple, stratified, specialized
simple squamous epithelium is a single layer of flattened cells specialized for _______ across their cytoplasm
diffusion
simple squamous are mainly found in _________, lining of ________, and structures in the _______
air sacs of the lungs, blood vessels, kidney
simple cuboidal appear in a single layer of square like shapes and function in ________, _________, ________ and _______
protection, secretion, absorption, synthesis
simple cuboidal cells are mainly found in the lining of the ________, where they help in the __________
collecting tubules of the kidney, reabsorption of water
simple columnar appear taller than they are wide and function in _______, _________, ________ and _________
protection, absorption, transport of materials, secretion
columnar cells lining the stomach secrete ________ that serves as a ________ for near by cells
mucus, protective barrier
simple columnar are found in the _____ tubes of the _____, ________ tubes, and the lining of the ______ and _______
bronchial, lungs, uterine, stomach and intestinal tract
stratified epithelium is composed of ______
more than one layer of cells
in stratified epithelium, only the ______ touches the basement membrane and the nuclei are ______
bottom layer, basically aligned with eachother
stratified cuboidal and columnar epithelium is a rarer type of stratified epithelium usually found in ________ and the ________
larger glands, male urethra
stratified cuboidal epithelia line the __________ that recycle sodium and chloride ions
ducts of sweat glands
stratified columnar epithelia in the ________ protect tissue from ______ by secreting mucus
male urethra, urine
stratified squamous are found in the ________, _______, ______, and _______
vocal folds, esophagus, vagina, epidermis of the skin
stratified squamous is adapted for _______, and are usually found in areas that undergo _________
toughness, friction
stratified squamous synthesize ______ to enhance cell toughness
keratin
the stratified squamous in the upper layers may ________ cellular organelles including the _______, this is usually found in the cells closest to the _______
eject, nuclei, lumen
pseudo-stratified epithelium has cells of different ______ and ______ and may appear the cells are in layers; however all cells _____ the basement membrane
shapes, sizes, touch
the respiratory pseudo-stratified epithelium contains ________, ________ and _______
columnar cells, basal cells, goblet cells
transitional epithelium (urothelium) is another form of __________, found in the _______ and _____
pseudo-stratified epithelium, bladder, ureter
urothelium functions to maintain a _______ barrier to keep ______ stored, even when the organ is distended
urinary, urine
urothelium has two distinct appearances, a _______ version and a ______ version
condensed, tall
urothelium has unique rounded cells called ________ whose dense _______ help maintain barrier function
umbrella cells, plaques
dome shaped umbrella cells can have _______
multiple nuclei
epithelial cells are ____ which means they have asymmetric distribution of proteins and organelles within their _________
polar, cytoplasm
polarity of a cell is defined by the three domains called the ______, ______, and _______
apical, basal, lateral
the apical domain faces the ________, and contains proteins that serve as ______, ________, and _______ that allow interactions with the ________
lumen, transporters, receptors, channels, lumen
The three important apical specializations include _______, _______, and ______ which help to increase ________ or help _______ substances along the epithelium surface
cilia, microvilli, stereocilia, surface area, move
microvilli are short finger like projections of ________ length along the apical surface that are enclosed by a _________
uniform, plasma membrane
microvilli are present in cells specialized for _______
absorption
microvilli are supported by __________ which insert into a network of cytoskeletal proteins referred to as the _______, a fuzzy border can be seen which is actually _______
actin filaments, terminal web, glycocalyx
cilia are longer hair like apical specializations that are _______ as uniform in length
NOT
Cilia have an internal array of ________ arranged in a _______ pattern
microtubules, 9+2
cilia are specialized for _______, where attached to their outer microtubule pairs are _______ proteins which allow cilia to move
motility, dynein moter
primary ciliary dyskinesia is a recessive genetic disorder where ciliary microtubules lack ______ and are therefor not motile (all cilia in the body are effected) this then causes cilia in the respiratory system to have problems _______ which leads to chronic ________ and ________
dynein arms, clearing mucus, sinusitis, bronchitis
stereocilia are non-motile, longer, have a ___________ structure and have a core of _________ that attach to a terminal web
branch like, actin filaments
stereocilia is rarer and found in the ________ and ________
epididymis , inner ear
the basal domain conatins the ________, _________ and _______
basement membrane, hemidesmosomes, basal infolding (striations)
the basement membrane functions as ________ support for the epithelium and ________ site for the lamina propria
structural, attachment
the basement membrane is a _________ filter where mutations cause _______ disease due to filtration compromise
semipermeable, kidney
the important macromolecules of the basement membrane include ________ fibers, ______ and _______ proteins
collagen, laminins, integrin
In electron microscopy, the basement membrane appears in two layers called the ______ lamina and the ______ lamina
reticular, basal
the basal lamina is where the base of the __________ cell is attached, and contains molecules that act as a ________ barrier
epithelial, permeable
the reticular lamina is a fibrous mesh that provides structure and attached the ________ to the _________
basal lamina, lamina propria
the basal lamina contains lamin, fibronectin, type _____ collagen, _______ sulfate proteoglycans, and _______
IV, heparan, nidogen (entactin)
the reticular lamina contains type ____ collagen
III
hemidesmosomes attach the ______ domain to the _______
basal, basal lamina (BM)
hemidesmosomes consist of protein ______ that anchor structures of the cell
plaques
intracellular plaques of hemidesmosomes inside the cell bind to keratin __________ filaments of the cytoskeleton
intermediate
extracellular domains of hemidesmosomes including ______ and ______ bind to molecules in the basal lamina
integrins, laminins
the lateral domain is the site of attachment to other cells in the epithelial sheet and is the avenue of ______ for materials
transport
the paracellular pathway is located _______ epithelial cells and is regulated by certain proteins
between
occluding junctions or _________, seal cells together and control the ______ of substances through the paracellular pathway
tight junctions, transport
adhering junctions include _______ and ______ which function to mechanically _______ cells together or to the _______
zona adherens, macula adherenes (desmosomes), attach, extracellular matrix
communicating junctions or _______, mediate the passage of ________ or _______ from one cell to thee other
gap junctions, chemical, electrical signals
tight junctions form seals that prevent proteins from ___________ and limit transcellular ________ and are associated with _____ filaments
migrating to other domains, transport, actin
tight junctions (zona occuldens) are formed by transmembrane proteins ______ and _______ and are associated with ______ filaments inside the cell and bind to ______ outside the cell
claudins, occludins, actin, each other
zona adherins are junctions that ______ and stabilize the sheet
attach cells together
zona adherens use ______ outside the cell to attach plasma membrane together and ______ filaments inside the cell
cadherins, actin
Desmosomes (macula adherens) form a series of attachment sights that stabilize the epithelium which are important in ______
skin
outside of the cell, desmosomes hold adjacent plasma membranes together by _______ and _______
desmocollins , desmogleins
inside the cell, desmosomes use thick protein plaques as insertion points for ________ filaments of the cytoskeleton
intermediate
Pemphigus, is a blistering disease where individuals make antibodies that bind and disrupt ______ which results in severe blistering
desmosomes
Gap junctions consist of transmembrane ________ proteins that form channels between cells called _______
connexin, connexons
Gap junctions permit the flow of _____ and ______ molecules for _________ communication between cells
ions , small, electrochemical
_____ connexin proteins form one connexon, and ______ connexons form a gap junction
six, two
