Flashcards in sem 1: Functions Deck (34):
1
what does the vagal reflex inhibit
smooth muscle tone
2
where are mechanoreceptors found for fundic relaxation
lower oesophagus
fundic area
3
what two things are involved with fundic relaxation
VIP (vasoactive intestinal peptide)
NO
4
what does the antral region of stomach do
mixes/grinds food with gastric secretions
5
what does the pyloric sphincter act as
sieve- only allows food particles of a certain size through
6
what does gastric juice contain
mucus
pepsinogen
intrinsic factor
lipase
7
what does mucus do
secreted by goblet cells and mucus neck cells- acts as a lubricant
8
what does lipase do
converts triglycerides into fatty acids and glycerol
9
what does pepsin do
secreted by chief cells and in involved in protein digestion
10
what does intrinsic factor do
secreted by parietal cells- needed for vitamin b12 absorption
11
what is HCL secreted by and used for
parietal cells
important in defence
conversion of pepsinogen to pepsin
12
what is a paracrine secretion
local hormones- secreted from cells in the mucosa but chemical acts locally on adjacent cells via the interstitial fluid
13
example of paracrine secretion
somatostatin
14
what does somatostatin do
inhibits gastrin release in the stomach (controls release od acid)
15
what are three examples of exocrine secretions
salivary glands
gastric glands
pancreas
liver
16
what is an exocrine secretion
secretes in a duct
17
what does the salivary glands secrete
mucus- provides lubrication for mastication and speech
18
what do gastric glands secrete
hcl
pepsin
mucus
19
what does the pancreas release
bicarbonate ions- neutralise of acids in chyme
amylase
lipase
carboxypeptidase
20
what does the liver secrete
bile acids- emulsification of fats
21
what is an endocrine secretion
secretion straight into the blood- travel to target tissue
ductless glands
22
examples of endocrine secretions
gastrin
secretin
pancreozymin/cholecytstokinin
insulin
23
what does gastrin do
secreted by G cells in the antrum
important in motility
24
where is secretin secreted
duodenal mucosa
25
where is pancreozymin/cholecytstokinin secreted
duodenal mucosa
helps contract liver to release bile for lipolysis
26
what does insulin do
secreted by pancreas by beta cells
27
where does absorption mainly occur
small intestine
28
where does fluid absorption occur
small intestine
colon
29
in what case would diarrhoea occur
if passes too quickly, faeces will be watery as not enough time for absorption
30
where do indegestible food residues leave the body in
faeces
31
drugs and some products of normal metabolism leave body in (4)
vomit
faeces
bile
saliva
32
what is the largest lymphoepithelial organ
intestine
33
defence mechanisms(5)
-sight/smell/taste
-vomit reflex
- HCL
- natural bacterial flora
- aggregation of lymphoid tissue (peyers patches)
34