Histology Flashcards
what are the 4 major layers of the GI tract from lumen?
mucosa > submucosa > muscularis externa > serosa/ adventitia
what is the mucosa layer made up of?
epithelium, lamina propria, muscularis mucosae
how many layers of SM does the muscularis externa have?
2 - 1 longitudinal, 1 circular
True/False…
oropharynx, laryngopharynx and oral cavity are covered by stratified squamous epithelium
True
what epithelium is the nasal cavity and nasopharynx covered by?
respiratory epi
does the anterior or posterior side of tongue have papillae?
anterior dorsal side
what are the 4 types of papillae?
fungiform, circumvallate, foliate, filiform
what is the pharynx composed of>
rings of lymphoid tissue
what is the histology of the oesophagus?
has a thick muscularis externa and glands
stratified squamous epithelium transitions to what other type of epithelium at the gastro-oesophageal junction?
changes to simple columnar epithelium
what do gastric pits have?
mucous cells and gastric glands
what is the additional layer of the muscularis externa of the stomach?
an additional oblique layer to aid churning
what are the gastric cell types in the isthmus?
parietal and stem cells
what are the cell types in the neck of the stomach?
neck mucous cells and parietal cells
what are the cell types of the fundus of the stomach?
chief cells and enteroendocrine cells
what do chief cells do?
secrete digestive enzymes
what do parietal cells do?
produce HCl
the SI contains villi and…
the crypts of liperkuhn (pits between the villi)
duodenum contains ________ Glands that produce a thin ____ mucous to neutralise the ____
Brunners Glands
thin alkaline mucous
neutralise the chyme
True/False…
the jejunum has the shorter villi
False…
jejunum= longest
ileum= shorter
what are Peyer’s Patches and where are they found?
lymphoid follicles found in submucosa of ILEUM
what are the 5 types of cell types found in the SI?
enterocytes (tall columnar cells which absorb) goblet cells (produce mucous) paneth cells (defensive cells which regulate bacterial flora) enteroendocrine (produce hormones) stem cells (replenish epithelium)
what are 2 main cells found in large intestine and their function?
absorptive cells: removes salt and water
goblet cells: secrete mucous
the outer longitudinal SM is found in 3 muscular strips called….?
Taenia Coli
In the appendix are crypts more or less abundant?
less
what is the epithelium of the anal canal like?
non-keratinised stratified squamous epi
what are the 2 plexuses of the enteric nervous system & what does each control?
myenteric plexus: controls gut motility
submucosa plexus: controls muscularis mucosa ie. secretions
what is the liver capsule?
a collagenous connective capsule
what shape are liver lobules?
hexagonal
each liver lobule has a centrolobular hepatic vein at the centre and a ___ at each corner?
portal triad
what is part of the portal triad?
hepatic vein, hepatic artery, bile duct which enter at portal hepatis
what is the space of Disse?
space between sinusoids and hepatocytes
what are sinusoids
fenestrations which allow blood to access all hepatocytes
what 3 cells are found in the liver and their functions?
hepatocytes: main cell of liver
hepatic stellate cells: modified fibroblasts found in space of Disse
Kupffer cells: found in sinusoids (remove red blood cells)
what epithelium is the gall bladder lined by?
simple columnar epi
in the pancreas the ____ __ _______ produce hormones and hence carry out the pancreas’s endocrine function?
islets of langerhans
what are the duct cells found in acini called?
centroacinar cells
the main pancreatic duct joins the common bile duct and opens into the duodenum, what is this opening called?
hepatopancreatic ampulla
