Lab 9: digestive system II Flashcards
name parts of stomach - 4
fundus
cardia
body
pylorus
describe muscosa of stomach - gen
pits and glands
Epithelium
lamina propria
muscularis mucosa
Smooth muscle projections in between glands in lamina propria
describe epithelium (muscosa of stomach)
simple columnar epithelium - surface mucous cells
describe lamina propria (muscosa of stomach)
loose irregular ct
describe muscularis mucosa (muscosa of stomach)
2 layers of smooth muscle = inner circular and outer longitudinal
sometimes 3 layers - outer circular
describe submuscosa of stomach
dense irregular ct
no glands
rich in blood vessels, lymphatic’s and nerves
describe tunica muscularis of stomach
3 layers of smooth muscle = inner oblique, middle circular, outer longitudinal
describe serosa of stomach
thin layer of loose ct covered by a mesothelium - simple squamous epithelium
what is unique to stomach
pits and glands
describe glands (of pits and glands)
glands are simple and unbranched
how are pits and glands connected
connected to each other via an isthmus/neck
describe pits
covered by surface mucous cells
the stomach lining is made up of this cell type
columnar in shape and have basally located nucleus that is ovoid in shape
apex of cell is filled with mucigen droplets (poorly stained with H&E)
cells are not goblet shaped
describe isthmus/neck region
glands narrow
have mucous neck cells present (like surface mucous cells but more pyramidal than columnar shape)
have stem cells (different from SI, result=bi directional orientation of differentiation)
glands are all made of mucous cells
describe what lamina propria does (glands)
fills in space between glands
describe parietal cells
in neck and base of gland
very eosinophillic and round
central nucleus (fried egg)
describe zymogenic cells
accumulate at base of gland
columnar shaped cell with ovoid nucleus (basally located so base appears basophilic)
apex of cell is filled with zymogen granules (eosinophilic, often poorly fixed)
what is function of parietal cells
secrete HCl
what is function of zymogenic cells
zymogen granules containing digestive enzymes
like lipases and pepsin
which cell types do we not have to identify
stem cells
enteroendocrine cells - requires special staining