Gastrointestinal Physiology Flashcards
Plexus controlling the motility of the GI smooth muscle
myenteric plexus
Auerbach’s plexus
Plexus controlling secretion and blood flow
submucosal plexus
Meissner’s plexus
Most potent amino acid stimuli for gastric secretion
phenylalanine
tryptophan
Where is gastrin released?
G cells in antrum
Where is CCK released?
I cells in duodenum and jejunum
What lipids stimulate secretion of CCK?
Not triglycerides (cannot cross intestinal cell membrane)
Where is secretin released?
S cells in duodenum
Only GI hormone that is released in response to fat, protein and carbohydrates
GIP
Slow waves are least frequent in
stomach
Slow waves are most frequent in
duodenum
Relaxes GI smooth muscle
VIP
Tonicity of saliva
hypotonic
Tonicity of pancreatic secretion
isotonic
Second messenger for secretin
cAMP
Second messenger for CCK
IP3 and Ca2+
Which lipid is not contained in micelles
glycerol
Site of secretion of intrinsic factor
fundus
The autonomic nervous system controls gut motility by changing which of the following? A) Pacemaker discharge frequency B) Slow wave frequency C) Spike potential frequency
spike potential frequency
What is the effect of hyperosmotic solution in the intestine on acid secretion?
inhibit
What is the effect of isoosmotic solution in the intestine on acid secretion?
no effect
muscle layers of the stomach
inner oblique
middle circular
outer longitudinal
most potent stimulti for gastrin secretion
phenylalanine
tryptophan
methionine
depolarization of slow waves
sodium influx
depolarization of spike potentials
calcium influx
satiety center
ventromedial thalamus
appetite/hunger center
lateral thalamus
anorexigenic neurons
POMC
orexigenic neurons
neuropeptide Y
anorexigenic substance
ghrelin
parotid gland secretes what type of secretion?
serous
submandibular gland secretes what type of secretion?
mixed
sublingual gland secretes what type of secretion?
mixed
which gastric glands contain mucus neck cells, parietal cells and chief cells?
oxyntic glands (body)
which gastric glands contain G cells and mucus cells?
pyloric glands (antrum)
gastric cell secreting histamine
enterochromaffin-like cells
gastric cell secreting serotonin
enterochromaffin cells
majority of gastric acid secretion: cephalic phase, gastric phase or intestinal phase?
gastric phase
CCK-A receptors are found in
pancreas
CCK-B receptors are found in
stomach
Cholic acid and chenodeoxycholic acid are primary or secondary bile acids?
primary bile acids
deoxycholic acid is from cholic or chenodeoxycholic acid?
cholic acid
lithocholic acid is from cholic or chenodeoxycholic acid?
chenodeoxycholic acid
absorption of glucose and galactose from lumen to intestinal cell
SGLT-1
absorption of fructose from lumen to intestinal cell
GLUT-5
absorption of glucose, galactose and fructose from intestinal cell to blood
GLUT-2
is pepsin essential for protein digestion?
no
all lipids go to the lacteals except
small-chain fatty acids
Bile salts inactivate pancreatic lipase. What pancreatic coenzyme is secreted to prevent this from happening?
Procolipase
main site for water absorption
jejunum
Potassium is absorbed in __ and secreted in __.
Potassium is absorbed in small intestine and secreted in large intestine.
primary ion secreted in intestinal lumen
Cl-
where is iron absorbed?
duodenum
most of the nutrients are absorbed where?
jejunum
amino acids are cotransported with what ion?
Na+
dipeptides and tripeptides are cotransported with what ion?
H+