GI anatomy, pathophysiology and pharmacology Flashcards
The oesophagus delivers food from the mouth to the stomach, but has little active involvement in digestion & absorption. TRUE OR FALSE?
TRUE
Absorption mostly takes place in small intestine. TRUE OR FALSE?
TRUE
Large intestine reabsorbs water from indigestible products allowing solid waste to be expelled. TRUE OR FALSE?
TRUE
The gastric wall Multiple basal layers of
muscle allow churning of contents. TRUE OR FALSE?
TRUE
Oxyntic glands contain parietal cells which secrete acid. TRUE OR FALSE?
TRUE
What did chief cells secrete?
Pepsinogen, gastric lipase
What do G cells and D cells secrete?
G cells - Gastrin
D cells - Somatostatin
What does Enterochromaffin
Cells secrete?
Atrial natriuretic peptide (ANP)
Pyloric glands secrete gastrin. TRUE OR FALSE?
TRUE
How much gastric juice is secreted per day?
2000-3000ml
Carbonic anhydrase makes H2CO3 which dissociates into H+ and HCO3. TRUE OR FALSE?
TRUE
The Cardia and the pylorus both have sphinches which control entry to and exit to the stomach. TRUE OR FALSE?
TRUE
What is the purpose of the mucosa in the GI wall?
- Digestion and absorption of nutrients
What is the purpose of the submucosa in the GI wall?
- Distribution of nutrients to rest of body
What is the purpose of the muscularis in the GI wall?
- For movement of nutrients along the GI tract
Glandular cells that secrte various things and together does not form the gastric glands. TRUE OR FALSE?
FALSE
What do each of these cells secrete? Parietal cells Chief cells Mucous cells ECL Cells G Cells D Cells Enterochromaffin Cells
Parietal cells - HCL, intrinsic factor, vitamin B12
Chief cells - Pepsinogen, Gastric lipase
Mucous cells - Mucous, bicarbonates
ECL Cells - Histamine
G Cells - Gastrin
D Cells - Somatostatin
Enterochromaffin Cells - Atrial natriuretic peptide (ANP)
Oxytinc gland does not secret gastric acid. TRUE OR FALSE?
FALSE
K+/H+ ATPase isn’t controlled by calcium and by cAMP. TRUE OR FALSE?
FALSE
Gastrin binds to the CCKB receptor and Ach binds to M3 receptor. TRUE OR FALSE?
TRUE
CCKB and M3 activation leads to an increase in calcium. TRUE OR FALSE?
TRUE
How is gastric acid secretion regulated (Ach and gastrin)?
An increase in calcium, incraeses the number of proton K+/H+ ATPase and there by increases the amount of acid that is secreted
How do Prostangladins, histamine and somatostatins regulate gastric acid secretion?
Histamine - It binds to H2 receptors, this increases cAMP which leads to increased activity of K+/H+ ATPase, so we obtain more protons pumped out into the lumen of the stomach
Prostangladins - The prostangladins binds to EP2/3R receptors helps to decrease cAMP production this leads to a decrease in K+/H+ ATPase activity and less H+ are pumped into the lumen of the stomach so less gastric production
Somatostatin - Decreases cAMP and there by decreasing the amount of protons being pumped into the lumen of the stomach
Pyloric glands can be stimulated by high pH and by gastirc distention. TRUE OR FALSE?
TRUE