deck_608599 Flashcards
Types of glands
Exocrine – Products (enzyme, mucus, lipids, cell contents) released into duct system• Types: Merocrine, Apocrine, HolocrineEndocrine – Products (hormones) travel in blood to distant targetsParacrine – Products (hormones) travel in interstitial space to very close targets
Order of Ducts
Main duct - lobar/interlobular duct- intralobular (striated) duct-intralobular duct-intercalated duct -acinus/secretory portion
Types of exocrine secretion
Merocrine – secretory product delivered to apical surface of cell via membrane bound vesicles - fuse with plasma membrane - extrude contents via exocytosisEx) sweat glandsHolocrine – secretory product accumulates in maturing cell - apoptosis - secretory product and cell debris dischargedApocrine – secretory product released surrounded by cytoplasm and plasma membraneEx) mammary gland
Mucous Gland
mucin secreting• Viscous, polysaccarhide and glycoprotein• Mucinogen w/in vesicle -secreted as mucin - +H2O - mucus
Serous Gland
protein secretingWatery, salt and protein rich enzymatic activityZymogen granules store secretion
Mixed glands
contain both serous and mucus cellsEx) submandibular gland and sublingual gland
Organization of a large gland (mixed salivary gland)
Acinus Intercalated duct striated duct (only serous) excretory duct
Acinus make up (mixed gland)
Mucous cell – basal located nucleiSerous cell – pyramidal shapeSerous demilunessurrounded by myoepithelial cells
Intercalated duct
low cuboidal cellsmay be generative (contain stem cells), secretes bicarbonate, absorbs chlorideNo larger diameter that secretory cells/aciniMost evident in serous glands with modified secretions
Striated duct
only in salivary glands)- simple cuboidal cells gradually becoming columnarspecialize for after transport - help concentrate secretion (reabsorbs Na, secretes K+ and HCO3-)infoldings of plasma membrane contain mitochondria = striations
Parotid gland
purely serous secreting glandCharacterized by lots of adipose tissueLong, narrow intercalated ducts; large striated ducts
Submandibular
mixed secretory gland (mostly serous)Less extensive intercalated ductsSome serous demilunes
Sublingual
mixed gland (mostly mucous)Shortest striated duct… b/c less need for concentrating secretory product -less serous cellsLess intercalated ductsSome serous demilunes but mostly mucous acini (often tubular)
Saliva – protective and digestive functions?
Moistens oral mucosaMoistening dry food to aid swallowingFacilitate activity of taste budsBuffering content of oral cavity Digesting CHO’s alpha amylaseControl bacterial flora of oral cavity Maintenance of teeth
Sweat gland types?
Eccrine gland• Secretory portion – simple cuboidal/columnar and largerduct portion – double cuboidalAppocrine Gland – actually merocrine gland• Anal and axillary sweat glands
