accessory glands/ histology Flashcards
what is a gland
an organised cluster of secretory units
functions of digestive glands
lubrication
protection
digestion and absorption
portions of salivary gland
secretory and duct regions
two types of cells (acini)
serous and mucous
held together by myoepithelial cells
duct system in salivary gland
intercalated -> striated -> interlobular -> interlobar -> principle
three types of salivary gland
parotid
submandibular
sublingual
parotid gland produces
water (serous) solution, about 25% total
submandibular gland produces
both serous and mucous, 70% total
sublingual gland produces
mucous secretion, 5% total
main enzyme in saliva
alpha amylase
main components of saliva
proteins, glycoproteins, ions, water IgA
arrangement of cells in saliva
secreter portions arranged in acini with the 3 cell types
type of epithelium in salivary gland
stratified squamous
autonomic regulation of salivary glands
parasympathetic most important
ach stimulates primary secretion, get large amounts of watery saliva
pancreas exocrine structure
compound tubulocacinar gland
pancreas exocrine function
produces digestive pro enzymes
apex of acinar cells facing lumen is filled with pro enzyme secretory granules
pancreatic duct opening into duodenum
at the papilla of vater
cell type in liver
hepatocytes
where do blood cells enter and leave the liver
porta hepatis
also where bile leaves
triad structure in liver
portal areas have branches of the hepatic artery, tributaries of portal vein, interlobular bile ducts vein = biggest artery = smallest bile duct has more symmetrical wall sinusoids between hepatocytes
resident macrophages in liver
kupffer cells phagocytic breakdown of RBC liver response to infection, toxins, ischaemia mononuclear phagocytes
apical and basolateral borders of hepatocytes
basolateral (sinusoidal) = absorbs blood-borne substances and secretes plasma proteins
apical (canalicular) = borders the bile canaliculus, sealed at the sides by occluding unctions
function of hepatic stellate cells
protean, multifunctional and enigmatic
versatile mesenchymal cells
become activated in response to liver injury and repair
liver major functions
bile production
detoxification
major role in metabolism - carbohydrate, amino acid and lipid
breakdown of insulin and other hormones