GI 6 Flashcards
what does motilin do?
secreted by MO cells , they increase intestine motility
waht do MO cells do and where are they located
-stimulated by alkaline pH
-upper small intestine (duo)
-secretes motilin
what is “entero”
pertaining to the small intestine
what are accessory secretions?
What are pancreatic secretions and what influences it
infleunce: sight, taste, gastrin and parasympathetic neurons
releases digestive enzymes
enteropancreatic reflex
S cells
secretin - inhibits gastric acid secretion
- inhibits gastric motility too
-stimulates duct cells
chief cells
secretes the inactive form of the digestive enzyme, pepsinogen
zymogen
inactive form of digestive enzymes
parietal cells
two secretions
- HCL - acti vates pepsinogen into pepsin
- intrinsic factor - binds to vitamin B12, necessary for absorbtion of the vitamin
what does pepsinogen do
kills pathogens, denatures protiens
entroendocrine cells (G-cells)
G cells secrete the hormone gastrin into the blood
I cells: chloecystokinin (CCK)
regulates pancreatic enzyme secretion
regulates bile scretion
stimulated by fatty acids
inhibits gastric acid procution and motility like S-cells
K cells
(GIP) gastric inhibitory peptide
GLP-1: glucagon-like peptide
also inhibits gastric acid secretion and motility
L cells
large intestine role
store and concentrate fecal matter
what valve connects the small and large intestine
ileocecal valve (opens when food enters stomach) its called the gastroileal reflex
appendix role
stores gut bacteria (in case of illness)
what secretion in lare intestine
secretion: moslty just mucus
digestion: no digestion in large
-bacteria break down stuff a bit (fermentation)(gases/farts)
ALSO PRODUCES VIT K
what is motility like in the large intestine
slow (18-24hrs)
- segmental contractions
- haustral rolling or churning (caused by incomplete layer of the longetudinal muscles)
- mass peristalsis (reason you gotta poo after you eat)
