Epithelium

Epithelium

1. Simple

   • Squamous
     • Endothelial
       • Lines the heart, blood and lymph vessels
     • Non-endothelial
       • Lines mesothelium (cavities) such as Bowman's capsule, thins loops of Henle and pulmonary alveoli
   • Cuboidal
     • Protects surfaces (glands: ovarian, salivary and pancreatic)
   • Columnar
     • Ciliated
       • Oviduct
     • Non-ciliated
       • Protects wet surfaces
       • Nutrient absorption (intestines)
       • Secretion (convoluted tubules of kidney, gall bladder, oviducts, uterus)
       • Apical surfaces contain microvilli
   • Pseudostratified ciliated
     • Lines URT (mucociliary escalator)
       • Lots of goblet cells

2. Stratified

   • Stratified cuboidal
     • More robust protection (sweat glands exocrine glands)
   • Stratified Squamous
     • Keratinized
       • Protection from abrasion and dehydration of surfaces exposed to air (skin, hard palate)
     • Non-keratinized
       • Protection of moist surfaces exposed to outside that do not absorb digestion (esophagus, vagina, male/female urethra and cornea
   • Transitional
     • Lower URT (urothelium); stretching force and impermeable