sem 1: Functions Flashcards
(34 cards)
what does the vagal reflex inhibit
smooth muscle tone
where are mechanoreceptors found for fundic relaxation
lower oesophagus
fundic area
what two things are involved with fundic relaxation
VIP (vasoactive intestinal peptide)
NO
what does the antral region of stomach do
mixes/grinds food with gastric secretions
what does the pyloric sphincter act as
sieve- only allows food particles of a certain size through
what does gastric juice contain
mucus
pepsinogen
intrinsic factor
lipase
what does mucus do
secreted by goblet cells and mucus neck cells- acts as a lubricant
what does lipase do
converts triglycerides into fatty acids and glycerol
what does pepsin do
secreted by chief cells and in involved in protein digestion
what does intrinsic factor do
secreted by parietal cells- needed for vitamin b12 absorption
what is HCL secreted by and used for
parietal cells
important in defence
conversion of pepsinogen to pepsin
what is a paracrine secretion
local hormones- secreted from cells in the mucosa but chemical acts locally on adjacent cells via the interstitial fluid
example of paracrine secretion
somatostatin
what does somatostatin do
inhibits gastrin release in the stomach (controls release od acid)
what are three examples of exocrine secretions
salivary glands
gastric glands
pancreas
liver
what is an exocrine secretion
secretes in a duct
what does the salivary glands secrete
mucus- provides lubrication for mastication and speech
what do gastric glands secrete
hcl
pepsin
mucus
what does the pancreas release
bicarbonate ions- neutralise of acids in chyme
amylase
lipase
carboxypeptidase
what does the liver secrete
bile acids- emulsification of fats
what is an endocrine secretion
secretion straight into the blood- travel to target tissue
ductless glands
examples of endocrine secretions
gastrin
secretin
pancreozymin/cholecytstokinin
insulin
what does gastrin do
secreted by G cells in the antrum
important in motility
where is secretin secreted
duodenal mucosa
