Epithelial Tissue Flashcards
Where does the apical domain of an epithelial cell face?
exterior surface/lumen of an enclosed cavity or tube
What is endothelium? What is it made of?
lining of blood and lymphatic vessels
made of simple squamous epithelia
What are goblet cells?
mucus-secreting cell found lining intestines and respiratory tract; help protect and collect debris
Where are simple cuboidal cells found?
kidney tubules, glands and associated ducts, terminal bronchioles, covering ovary
What are occluding junctions?
junctions that encircle cells near most apical surface –> can create impermeability of a layer of cells
What are flagella? Where do you find them?
modified motile cilia
sperm tail
What are the 4 types of apical specializations?
cilia, flagella, microvilli, and stereocilia
What are gap junctions?
fluid-filled channels that connect cells and mediate communication
What are nodal cilia?
embryonic, have role in L/R axis determination
Where do you find keratinized stratified squamous cells?
epidermis of the skin
for barrier and protection
What are focal adhesions and hemidesmosomes made of?
integrins
What is the function of simple squamous epithelia?
exchange, barrier, and lubrication
What are motile cilia?
cilia that beat in a wave-like fashion to propel substances across tissue
What are stereovilli made of?
actin - provides rigidity
How do merocrine glands secrete?
secretion delivered in membrane-bound vesicles to apical surface –> exocytosis
What do mucous acini look like in stain?
very light, don’t take up dye
Where are urothelium cells found?
urinary blader, ureters, urethra
Where are pseudostratified columnar ciliate cells?
position of nuclei vary so it looks like multiple layers but is actually 1 layer
for absorption and secretion, debris and particulate movement
Where are simple squamous epithelial cells found? (5)
endothelium, mesothelium, lining alveoli in lungs, loop of henle in kidney, various ducts
What are hemidesmosomes?
intercellular junctions that anchor intermediate filaments to basement membrane
What are simple cuboidal cells? What is their function?
1 layer thick w/ round nuclei that make a tube
absorption, barrier, secretion
What is mesothelium? What is it made of?
lining of serous membranes
made of simple squamous epithelia
Where are nonkeratinized stratified squamous cells found?
oral cavity, portions of pharynx, esophagus, anus, vagina urethra, cornea
basically where there is friction and abrasion not on outermost skin
Where are pseudostratified columnar ciliate cells found?
lining of nasal cavity, pharynx, trachea, bronchi
What are occluding junctions made of?
occludins, claudins
What are cilia made of?
microtubule based
What are stereovilli/stereocilia?
microvilli of unusual length - long and immotile
What are zonula adherens and what do they interact with?
type of anchoring junction
connect actin filaments cell to cell
What is a serous membrane?
epithelial tissue that lines specific internal cavities of body
forms smooth 2 layered membrane
lubricated by fluid derived from serum
mesothelium is part of a serous membrane
Where are simple columnar cells found?
auditory tubes, uterus, oviducts, stomach, intestines, gallbladder
What is special about urothelium cells?
dome shaped cells at apical surface
stratified epithelium that allows for stretch and recoil of bladder
What is the function of simple columnar cells?
absorption and secretion
What does the lateral domain of an epithelial cell face?
adjacent cells
What are anchoring junctions made of?
cadherins
What are anchoring junctions?
lateral adhesions that link into cytoskeleton of adjacent cells
zonula adherens
macula adherens/desmosomes
How do apocrine glands secrete?
(mammary glands) release of apical portion of cell w/ cytoplasm in plasma membrane
Where do you mainly find cilia?
in the respiratory tract
What are primary cilia?
immotile cilia, function as chemosensors, osmosensors, mechanosensors
What do serous acini look like in stain?
very dark, take up dye heavily
What are gap junctions made of?
connexin
What type of epithelia is one layer thick?
simple epithelia
What is special about the apical layer of keratinized stratified squamous cells?
do not have nuclei
what is the basal domain of an epithelial cell to?
basal lamina; anchors cell to underlying connective tissue
Where are stereovilli/stereocilia restricted to?
epididymis and sensory cells of inner ear
What is the purpose of microvilli?
increase surface area of apical domain by 20-30x –> increase absorption
What are microvilli made of?
actin core
How do holocrine glands secrete?
secretion accumulates w/in cell –> apoptosis –> secretion and cell debris released
What are macula adherens/desmosomes and what do they interact with?
type of anchoring junction
connect intermediate filaments in adjacent cells
What are focal adhesions?
intercellular junctions that anchor actin filaments to basement membrane
What type of epithelia is more than one layer thick?
stratified epithelia
Where are stratified cuboidal cells found?
sweat glands and ducts, ovarian follicles, salivary gland ducts
passageway function is important!
