010714 biochemical and nutrition for stomach Flashcards Preview

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Flashcards in 010714 biochemical and nutrition for stomach Deck (20):
1

components of saliva

salivary gland secretions
microorganism products
soluble food products

2

purpose of saliva

lubrication
digest food and enzymatic cleavage
growth factors for epithelial cells
neutralizes bacterial acids
mediates taste sensations
provides defense against bacterial pathogens

3

primary secretion of salivary gland has

ptyalin (alpha amylase)
mucus
extracellular fluid (ions)

4

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)

peroxidase
lactoferrin (binds iron and prevents bacterial growth)
IgA
defensins
mucins

5

mucin's role

lubricates
antimicrobial

6

saliva's ionic content is high in what and low in what

high in bicarbonate--it neutralizes bacterial acids

low in Na and Cl

7

cephalic phase of gastric secretion

parasympathetics excite pepsin and acid production

8

gastric phase of gastric secretion

local nervous secretory reflexes
vagal reflexes
gastrin-histamine stimulation

9

intestinal phase of gastric secretion

nervous mechanisms
hormonal mechanisms

10

stomach's acid secretion is regulated how?

vagus nerve releases Ach and GRP

11

what are ACh's effects?

stimulates secretion of ECL cell histamine and parietal cell HCl

inhibits secretion of D cell somatostatin

12

What are GRP's effects

stimulates secretion of G cell gastrin

13

control of D cells occurs through?

somatostatin secretion is stimulated by HCl and inhibited by ACh

14

somatostatin's effects?

inhibits secretion of G cell gastrin, ECL cell histamine, and parietal cell HCl

15

gastrin secretion is controlled how?

stimulated by nerve's GRP
inhibited by somatostatin

16

gastrin's effects

stimulates secretion of D cell somatostatin, ECL CELL HISTAMINE, parietal cell HCl

17

parietal cell HCl secretion is inhibited by

D cell somatostatin

18

how is pepsinogen secretion controlled?

secretion is induced by ACh, gastrin, secretin, and CCK

19

fxn of mucous

lubricates
protects by providing HCO3 to neutralize acid within mucous

20

food in strecthing the stomach causes what reflex?

vasovagal reflex to relax stomach wall