Epithelia Sub Types Flashcards
Simple cuboidal
Location: glands, kidney tubules
Morphology: cuboidal, varied height
Function: active transport, excretory, secretory and absorptive
Simple squamous
Location: lungs, blood vessel walls
Morphology: flat, thin, irregular, only visible from bulge of nucleus
Function: passive diffusion from underlying tissue
Simple columnar
Location: uterus lining, most digestive tract organs
Morphology: tall, very polarised (nuclei at bottom)
Function: absorptive, secretion
Pseudostratified columnar
Location: respiratory passage
Morphology: stretch –> reveal simple, nuclei at different levels
Function: active transport
Glandular epithelial
Invagination
Cuboidal or columnar
Keep surfaces moist
Multi- or uni-cellular
Stratified squamous non-keratinised
Location: throat, mouth, vagina
Morphology: cuboidal –> flattened
Function: protection against abrasion
Stratified squamous keratinised
Location: epidermis
Morphology: cross linked cytokeratin intermediate filaments, nuclei progressively condense
Function: protects against water loss, sloughed off from abrasion, continually replaced
Stratified cuboidal/columnar
Location: salivary, mammary glands
Function: robust linings
Rare
Transitional/urothelium
Location: urinary tract
Morphology: upper layer most flattered when stretch led by fluid. Superficial layer “umbrella cells” contain uroplakins, line luminal surface
Function: protection against urine. Very stretchy and expansive, accommodates fluctuation in volume
