Lecture 4: Epithelial Tissue I Flashcards
Apical domain of epithelial cell
Surface of cell in contact with lumen or external environment; demonstrates cellular POLARITY
Basolateral domain of epithelial cell
Surfaces of cell locked together with other cells by junctional complexes, as well as surface opposite apical domain which is in contact with the basal lamina; demonstrates cellular POLARITY
Basement membrane
2 components: basal lamina and reticular lamina Functions: selective filtration barrier, scaffold for regeneration, stabilization of tissue shapes
Cilia
Core of microtubule doublets in a 9+2 concentric arrangement surrounded by plasma membrane Multiple motile: coordinate fluid or cargo flow on surface of epithelium; present in trachea, oviduct Single, non-motile: sensor for external environment, embryonic patterning, hedgehog signaling; associated with ciliopathies
Microvilli (brush border)
Core of cross-linked microfilaments; found in intestinal epithelium and portions of kidney nephron; indicates absorptive function of cells
Stereocilia
Core of cross-linked actin/filaments; NO axonmemes; present in lining of epididymis, contribute to process of sperm maturation; OFTEN BRANCHED
Where is simple squamous epithelium found?
Lines lumen of ducts, vessels tubular structures; forms walls of alveoli, Bowman’s capsule, inner surface of membranous labyrinth and tympanic membrane
Where is simple cuboidal epithelium found?
Ovarian surface, pigmented retina epithelium, kidney tubules, glands/ducts, terminal bronchioles, choroid plexus, anterior capsule of lens of the eye
Where is ciliated columnar epithelium found?
Upper respiratory tract, uterine tubes, uterus, paranasal sinuses, central canal of the spinal cord
Where is non-ciliated columnar epithelium found?
digestive tract beginning with cardia of the stomach, gall bladder, parts of excretory ducts of glands
Where is heavily keratinized stratified squamous epithelium found?
Epidermis with connective tissue papillae, cornea without connective tissue papillae
Where is lightly/non-keratinized stratified squamous epithelium found?
esophagus, vagina, lining of mouth, tongue, part of epiglottis
Where is stratified cuboidal epithelium found?
RARE - may occur in anal mucosa, large excretory ducts, male urethra
Where is stratified columnar epithelium found?
RARE - occurs in ducts of sweat glands, fornix of conjunctiva, male reproductive/urinary tract, pharynx, epiglottis
Where is pseudostratified epithelium found?
Ciliated - trachea With stereocilia - epididymis
Stratified Squamous
Non-keratinized
Stratified Squamous
Heavily keratinized
Simple Cuboidal
Stratified Squamous
Non-keratinized
Simple Cuboidal
Simple Columnar
Transitional
Simple Columnar
Pseudostratified Columnar
Simple Cuboidal
Transitional
Simple Cuboidal
Simple Columnar
Transitional
