gritti lesson 14 Flashcards
major 3 glands that secretes 90% of the total saliva
parotid
submandibular
sublingual
how much saliva do we produce in one day?
1 L
minor glands in the oral mucosa that produce 10% of the total saliva
lingual, buccal, palatal, labial
-scattered across the oral mucosa
what is the epithelium of the intercalated ducts in the salivary glands?
simple squamous
intercalated ducts merge into striated ducts in the salivary glands. what’s the epithelium of striated ducts?
between simple cuboidal and tall columnar
striated ducts merge into interlobular ducts in the salivary glands. what’s the epithelium of these ducts?
tall columnar epithelium
or
stratified cuboidal
or
stratified columnar
in general is pluristratified
intralobular vs striated
striated=parotid and submandibular
nuclei are towards the lumen
striations
intralobular=sublingual
nuclei not towards the lumen
bigger
what is an acinus?
a cluster of different types of secretory cells in a lobule around a central lumen.
each lobule contains multiple acini
the cells in an acinus can be
mucous
serous
myoepithelial cells
the main duct, the one that empties in the oral cavity, has which type of epithelium?
stratified nonkeratinized squamous epithelium
where do vessels and nerves enter into the salivary gland?
into the hilum and gradually branch into the lobules
which is the largest salivary gland?
the parotid, present in each cheek near the ear
gland parenchyma
functional component of the gland that present ducts and secretory cells
stroma
connective tissue that encapsulates the glands
is the parotid gland a mucous or serous gland?
mostly serous with scattered mucous cells
where can we find plasma cells in the parotid glands?
in the connective tissue that surround intralobular ducts. they derive from B lymphocytes and are responsible for IgA production, which has an important role in mucosal immunity
->provide defense of the oral cavity mucosa against pathogens
the serous demilune is a characteristic of which gland?
the submandibular
is the submandibular gland a mucous or a serous gland?
mostly serous, a small % of mucous cells
kinda 50-50
is the sublingual gland mostly mucous or serous?
mucous cells predominate
the pancreas
is a mixed endocrine and exocrine gland
which type of tissue are the islet of langherans in the pancreas? (endocrine or exocrine?)
endocrine tissue
embedded in the serous acini (exocrine tissue)
ductal system in the pancreas
intercalated ducts merge into intralobular ducts that merge into interlobular that merge into the main pancreatic duct
does the pancreas have myoepithelial cells?
no, it doesn’t.
we can find them in the salivary glands
centroacinar cells
intercalated duct cells at the center of the acinus
represent the passage between the secretory portion and the duct
type of epithelium of the intercalated duct in the pancreas and of intralobular ducts
simple squamous or cuboidal
simple cuboidal for intralobular ducts
type of epithelium of the interlobular duct in the pancreas
simple columnar, stratified columnar or stratified cuboidal
in the right lobe, the liver is supplied by two main vessels:
hepatic artery
portal vein
porta hepatis
the central hilum of the liver
COMPREHENDS
PORTAL VEIN
HEPATIC ARTERY
BILE DUCT
each lobule is surrounded by how many portal triads?
3-6
each portal triad is made of
an arteriole branch of the hepatic artery
a venule branch of the portal vein
one or two bile ductules, branches of the bile ducts
sinusoids
-capillary-like vessels of the liver.
-they have a discontinuous endothelium
they have a mixed of venous and arterial blood
-no basement membrane in the endothelium
kupferr cells
-lie in the liver sinusoids
-macrophage like cells
-they recognize and phagocytose aged herytrocytes
-they are antigen presenting cells and remove any bacteria present in the portal blood
perisinusoidal space or space of Disse
-between the fenestrated endothelial cells of the sinusoids and the hepatocytes
-It is part of the liver lobule structure, surrounding the sinusoids.
-the space is filled with plasma allowing an efficient exchange of nutrients
-The fenestrated endothelial cells and the lack of a basement membrane allow plasma to pass freely into the perisinusoidal space, facilitating direct contact with the hepatocytes.
The microvilli of hepatocytes interact with the plasma in this space for metabolic exchange.
hepatic stellate cells
-mesenchymal cells
-perisinusoidal space
-produce ECM components and cytokines that help the activity of the kupfer cells
-have droplets of lipids to store vitamin A
liver zonation
hepatocytes have different functions based on where they are positioned in the lobule
ig: the hepatocytes more inside get less oxygens and less nutrients (and so they perform different functions) than ones near the portal triads
bile canaliculi
apical surface of hepatocytes are sealed by tight junctions to form bile canaliculi
inside the bile canaliculi we have the passage of the bile that goes from the center of the lobule to the periphery
canals of Hering
-lined by simple cuboidal cells named cholagiocytes
-the bile from the bile canaliculi go into the canals of hering that then merge into the larger bile ductules
in the liver blood flow and bile flow are opposite
blood: from the periphery to the center
bile: from the center to the periphery
bile conduction system from smaller to bigger structure
bile canaliculi
canals of Hering
bile ductules
right and left hepatic ducts
common hepatic duct (in the Porta hepatis)
common hepatic duct+cystic duct= common bile duct
gallbladder
-folded mucosa (simple columnar epithelium)
-lamina propria
-muscolaris externa (one layer of smooth muscle with bundles of muscle fibers oriented in several directions to facilitate emptying
-adventitia (in the part attached to the liver) serosa in the exposed part
how is contraction of the muscolaris of the gallbladder stimulated (to release the bile into the duodenum)?
by the release of cholecistokinins from enteroendocrine cells in the small intestine.
enteroendocrine cells are stimulated by the presence of ingested fats in the small intestine
which type of duct is present in the salivary glands but is absent into the pancreas?
striated duct
in the pancreas instead we have intralobular ducts
in which tissue are you if you see centroacinar cells inside the acini?
PANCREAS
