105b end + 110-111b pancreas, liver, gall bladder Flashcards
function of goblet cells in intestine
lubrication
function of paneth cells and location in intestine
antibacterial
base of crypts
what secretes CCK and what does it do?
enteroendocrine cells in duodenum and jejunum and a little in the ileum
increases pancreatic secretions and gallbaldder contraction in response to fatty acids and protein
sphincter relazatioj
peyer’s patches
Unencapsulated lymphoid tissue found in lamina propria and submucosa of ileum. Contain specialized M cells that take up antigen. B cells make IgA - "Intra Gut Antibody" via transcytosis by enterocytes
Brunner’s glands
Located in duodenal submucosa.
Secrete alkaline mucus.
Hypertrophy seen in peptic ulcer disease.
Colon/large intestine histo
no villi
abudant goblet cells
tenia coli - consolidated muscle layers
what is the fundamental unit of the exocrine pancreas?
acinus - collection of secretory, brightly stained secretory cells
secrete zymogen granules
what exocrine substances are secreted by the pancrease?
trypsinogen -> tyrpsin via enterokinase in brush border
- chymotrypsinogen
- proelastase
- procaroxylase
- = activated by trypsin
centroacinar cell - apperance and function?
squamous shape extending into lumen of acinus
secretes HCO3-
what is the endocrine part of the pancreas?
islets of langerhans – highly vascularized area with hormones secreted into capillaries
what are the 3 major classes of pancreatic endocrine cells? what do they secrete? where are they located?
A=glucagon; peripheral (round granule with white space around)
B=insulin, central (granules with crystals)
D=somatostatin, interspersed (homogeneous granule)
liver cell arrangement
Apical surface of hepatocytes faces bile canaliculi.
Basolateral surface faces sinusoids.
liver zones
Zone I: periportal zone: -Affected 1st by viral hepatitis Zone II: intermediate zone. Zone III: pericentral vein (centrilobular) zone: -Affected 1st by ischemia -Contains P-450 system -Most sensitive to toxic injury -Site of alcoholic hepatitis
portal triad
portal vein
hepatic artery
bile ductule
**bile flows towards via bile canaliculi; blood flows away towards central vein (to heptic vein and systemic circulation)
kupffer cell
resident macrophage in the liver
type of endothelial lining in the liver and what is behind + cell?
sinusoid fenestrated w/ perisinusoidal space of disse behind for lymph (contain Ito/stellate cells storing vitamin A in lipid droplets)
bilirubin
Product of heme metabolism. Bilirubin is removed from blood by liver, conjugated with
glucuronate, and excreted in bile.
Direct bilirubin—conjugated with glucuronic acid; water soluble.
Indirect bilirubin—unconjugated; water insoluble.
Bile - composition
Composed of bile salts (bile acids conjugated to glycine or taurine, making them water soluble),
phospholipids, cholesterol, bilirubin, water, and ions (pigments). Cholesterol 7&-hydroxylase catalyzes rate-limiting step.
bile function
Digestion and absorption of lipids and fat-soluble vitamins Cholesterol excretion (body’s only means of eliminating cholesterol) Antimicrobial activity (via membrane disruption)
gall bladder function
concentrates bile from liver by pumping Na from apical PM (water follows)
gall bladder histo
simple columnar epi and lamina propria
no submucosa
irregular collections of smooth muscle