Stomach anatomy Flashcards
chief cells
secretes pepsinogen and gastric lipase
Parietal cells
secretes HCL and intrinsic factor (needed for B12 absorbtion)
enteroendocrine cells
Secretes hormones : gastrin ( G cells), Somatostatin)
gastric glands
contains pits which has glands that contains variety of cells.
made of simple columnar epithelium.
what waves in the stomach?
peristalsis that mix the food with gastric juices
how HCL secrete and 3 functions
secrete by Parietal cells.
Function : # denature proteins
# activate pepsinogen
# stimulate gastrin hormone
Describe Pepsin’s PH, how activated? how secreted? and its Substrate.
works best at Ph 2.00 ( in stomach)
secreted by chief cells
activated by HCL
substrate protein (breaks down proteins)
Gastrin Lipase
breakdown short to medium chain fatty acids (lipids)
describe Gastrin hormone, how secreted?
secreted by enteroendocrine cells.
in the stomach, chemoreceptors detect low ph and start in smooth muscle contractions, so food in the stomach ( coffee and protein) stimulate gastrin release.
In gastric secretion, what phases happen
Cephalic Phase: Stomach getting ready
Gastric Phase : Stomach working
Intestinal phase: Stomach emptying
Cephalic phase
by thought food smell, sight of food
Cerebral cortex > Medulla Oblongata > preganglionic nerve fibers of Vegus nerve > post G.N. fibers of Submucosal plexuses > stimulate gastric cells.
gastric Phase
- Stomach stretch
- Ph increase detect by chemoreceptors
- signal submucosal plexus to activate smooth muscles
- contraction occur as waive peristalsis
- food in the stomach stimulate the release of the Gastrin
Intestinal Phase
in the duodenum, gastrin released when chyme received by the duodenum
list three things absorbed in the stomach
Water
lipid soluble drugs
alcohol
