Flashcards in 010714 biochemical and nutrition for stomach Deck (20):
components of saliva
salivary gland secretions
soluble food products
purpose of saliva
digest food and enzymatic cleavage
growth factors for epithelial cells
neutralizes bacterial acids
mediates taste sensations
provides defense against bacterial pathogens
primary secretion of salivary gland has
ptyalin (alpha amylase)
extracellular fluid (ions)
what does the saliva contain for bacterial defense?
lysozyme (kills gram positive bacteria by cleaving beta 1-4 linkages between NAM and NAG in peptidoglycan)
lactoferrin (binds iron and prevents bacterial growth)
saliva's ionic content is high in what and low in what
high in bicarbonate--it neutralizes bacterial acids
low in Na and Cl
cephalic phase of gastric secretion
parasympathetics excite pepsin and acid production
gastric phase of gastric secretion
local nervous secretory reflexes
intestinal phase of gastric secretion
stomach's acid secretion is regulated how?
vagus nerve releases Ach and GRP
what are ACh's effects?
stimulates secretion of ECL cell histamine and parietal cell HCl
inhibits secretion of D cell somatostatin
What are GRP's effects
stimulates secretion of G cell gastrin
control of D cells occurs through?
somatostatin secretion is stimulated by HCl and inhibited by ACh
inhibits secretion of G cell gastrin, ECL cell histamine, and parietal cell HCl
gastrin secretion is controlled how?
stimulated by nerve's GRP
inhibited by somatostatin
stimulates secretion of D cell somatostatin, ECL CELL HISTAMINE, parietal cell HCl
parietal cell HCl secretion is inhibited by
D cell somatostatin
how is pepsinogen secretion controlled?
secretion is induced by ACh, gastrin, secretin, and CCK
fxn of mucous
protects by providing HCO3 to neutralize acid within mucous