GI phys Flashcards
what are the 3 types of gastric glands
Mucosal (neck) cells- secrete mucus and gastine
chief
parietal
what cells produce gastrin
G cells (in mucosal neck cells)
What doe chief cells produce/secrete
produce pepsinogen
(in presence of hydrochloric acid, pepsinogen is activated to form pepsin- necessary for pro digestion)
What do parietal cells secrete
secrete hydrochloric acid and intrinsic factor
What is HCL and intrinsic factor used for
HCL is needed for activation of pepsinogen
Intrinsic factor necessary for absorption of Vit B12
what does chyme in s intestine stimulate
stims release of secretin from S-cells found in duodenum
What does secretin do
stims pancreatic acinar cells to release bicarbonate and water
what does bicarbonate do
(also secreted by brunners glands, along with pancreatic ancinar cells)
-neutralizes the gastric acid and makes Ph alkaline
-protects duodenal walls
What does the presence of fat in duodenum stim
Cholecystokinin (CCK) by the I cells of duodenum
-CCK causes gallbladder to contract ad sphincter of Oddi to reps
what do the exocrine cells of the pancreas release
-Trypsinogen- activated by trypsin which starts pro digestion
-Pancreatic amylase- digestion of starch
-lipase- breaks down fat into fatty acids and glycerol
What are the endocrine cells releasing in pancrease
Arranged into the islets of langerhans:
-glucagon
-insulin
-somatostatin
What type of specialized cells of the Large intestine release
numerous goblet cells which secrete mucus to aid in passage of faces
What are the fat soluble vits
DAKE
where is folic acid and iron absorbed
in jejunumm
what transfers iron in blood to cells in the liver, spleen and bone marrow
transferrin
