Flashcards in 105b stomach and intestines histo Deck (12)
what are the folds inside the stomach when it's empty called?
rugae - due to contraction of muscularis mucosae
3 general regions of the stomach - top to bottom
how many muscles layers are in the stomach muscularis externa?
3 - inner oblique, middle circular, outer linear
what is the functional gland of the stomach?
gastric glands - mostly in fundic later
cell types of the gastric glands (top to bottom) and function
surface mucous cells (washed out, secrete mucous which coats surface and protects cells via mucinogen granules on apical side)
neck mucous cells (different type of mucous)
parietal cells (pink cells, secrete intrinsic factor (B12) + HCl, large pyramidal cells with many mito, extensive network)
chief cells (dark stain, secrete pepsinogen)
enteroendocrine cells (hormones secretion at basal surface)
regional difference in glands for the stomach - cardiac/pyloric vs fundic
fundic more parietal and chief cells
cardiac/pyloric more mucous cells with deeper pits
where are new are new gastric epithelial cells made?
isthmus - neck of gastric gland
what are the specialized structures in the intestine?
plicae circularis (mucose + submucosa)
villi (core has lamina propria with vessels and lacteal)
microvilli (part of enterocytes)
glands/crypts - invaginations
brunner's gland - location, function
in duodenal submucosa
secrete alkaline mucus
intestinal absorptive cell
simple columnar epithelial
microvilli (actin-bundle scaffold) at apical side
tight junctions seal off cell
lipid absorption in intestine
1) micelles w/ FFA (from lipases) enter via brush border
2) FFA re-esterified to make triglycerides and cholesteryl esters
3) combined with apo-lipoproteins to make lipoproteins (chylomicrons)
4) chylomicrons secreted to lacteals and capillaries