12: Epithelia Flashcards
Is epithelia capable of regeneration?
Yes
Vascularization and innervation of epithelia
Avascular, innervated
Core of microvilli and stereocilia vs cilia
Microvilli and stereocilia: core of actin
Cilia: core of microtubules
Celiac disease
Loss of microvilli on absorptive cells of SI
What are stereocilia?
Long + less mobile microvilli
Two locations stereocilia are restricted to
Hair cells of inner ear, epididymis
Three types of cilia and their functions
Motile: beat in a wave to propel substances
Primary: immotile, for chemosensing and cell signaling
Nodal: embryonic, role in L/R axis
Mucous membrane vs serous membrane
Mucous: epithelial tissue that secretes mucus
Serous: epithelial tissue that lines internal body cavities
Three examples of serous membranes
Peritoneum, pericardium, pleura
Mesothelium
Simple squamous ep that lines a serous membrane
Five locations of simple squamous ep
- Endothelium (blood and lymph)
- Mesothelium
- Lining alveoli
- Loops of Henle
- Various ducts
Four locations for simple cuboidal ep
- Kidney tubules
- Glands and ducts
- Terminal bronchioles
- Covering ovary
Six locations for simple columnar ep
- Auditory tubes
- Uterus
- Oviducts
- Stomach
- SI/LI
- Gallbladder
Where is pseudostratified columnar ciliated ep found?
Respiratory tract: nasal cavity, pharynx, trachea, bronchi
Where is urothelium (transitional ep) found?
GU system; bladder, ureters, urethra
Unique property of urothelium
Is distensible - can stretch and recoil as needed
Seven locations of non-keratinized stratified squamous ep
- Oral cavity
- Pharynx
- Esophagus
- Anus
- Vagina
- Urethra
- Cornea
Location for keratinized stratified squamous ep
Epidermis
Three locations for stratified cuboidal and columnar ep
- Sweat gland ducts
- Ovarian follicles
- Salivary gland ducts
Unicellular glands
Single secretory cells distributed among non-secretory cells
Example of unicellular glands
Goblet cells in intestines and resp tract
Exocrine glands
Multicellular glands comprised of secretory cells grouped into acini
Product secretion in exocrine glands
Produce secreted into a system of ducts for release
Parenchyma vs stroma
Parenchyma: the functional tissue of an organ or gland
Stroma: CT support
Two examples of stroma
Septa, capsule
Merocrine secretion
Membrane-bound vesicles exocytosed from apical surface
Apocrine secretion
Release of secretion, apical portion of cell, and some cytoplasm
Holocrine secretion
Apoptosis of cell -> secretion of product and cell debris
Examples of merocrine, apocrine, and holocrine secretion
Merocrine: salivary glands
Apocrine: mammary glands
Holocrine: skin glands (idk which kind)
Simple vs compound glands
Simple: unbranched ducts
Compound: 2+ branches
