ILA 5 - Gastro SBA Flashcards
You are trying to design a drug to act on histamine receptors on parietal cells to help patients with reflux disease.
What would be the mechanism of this drug?
A. Inhibits both Histamine 1 and Histamine 2 receptors to reduce acid secretion
B. Inhibits Histamine 1 receptors to reduce acid secretion
C. Inhibits Histamine 2 receptors to reduce acid secretion
D. Stimulates Histamine 1 receptors to stimulate acid secretion
E. Stimulates Histamine 2 receptors to reduce acid secretion
C. Inhibits Histamine 2 receptors to reduce acid secretion
The parietal cells within the stomach produce Intrinsic factor.
What is the function of Intrinsic Factor?
A. Allows absorption of Vitamin B12 in the terminal ileum
B. Blocks absorption of Vitamin B12 to prevent B12 overdose
C. Cleaves Vitamin B6 to form Vitamin B12
D. Protects Vitamin B12 from degradation by stomach acid
E. Stimulates secretion of Vitamin B12 into the bowel lumen
A. Allows absorption of Vitamin B12 in the terminal ileum
(Gastric) Intrinsic Factor is a glycoprotein produced by the parietal cells of the stomach and is essential for the absorption of Vit B12.
It binds with Vit B12 and forms a complex that resists digestion by gastric enzymes.
The Vit B12 complex then passes through the stomach where it absorbed in the terminal ileum, transported to the liver and stored.
A 56 year old man has a long standing history of gastro-oesophageal reflux.
What is the change in cell-type (‘metaplasia’) seen in the lower oesophagus after prolonged reflux of acid?
A. Columnar to pseudostratified columnar
B. Columnar to stratified squamous
C. Cuboidal to columnar
D. Pseudostratified columnar to columnar
E. Stratified squamous to columnar
E. Stratified squamous to columnar
Digestion of the different dietary components occurs in different parts of the GI tract.
What is the first location that fat is acted upon by Lipase enzymes when passing through the GI tract?
A. Duodenum
B. Ileum
C. Oesophagus
D. Oral cavity
E. Stomach
D. Oral cavity
The stomach contains a variety of cell types.
Which of these substances is secreted by Chief cells?
A. Cholecystokinin
B. Chymotrypsinogen
C. Pepsinogen
D. Saliva
E. Somatostatin
C. Pepsinogen
A 40 year old has been diagnosed with gallstones, one of which is in the common bile duct.
Where does the Common Bile Duct drain into?
A. Caecum
B. Duodenum
C. Gallbladder
D. Lesser sac
E. Stomach
B. Duodenum
Omeprazole is routinely prescribed for acid reflux.
What is the mechanism of action of Omeprazole on the GI tract?
A. Blockade of Vagus nerve activity on the stomach
B. Direct neutralisation of stomach acid
C. Inhibit pancreatic proteases to protect lining of the duodenum
D. Inhibition of Proton Pump to reduce acid secretion
E. Stimulation of CCK receptors to increase bile secretion
D. Inhibition of Proton Pump to reduce acid secretion
The stomach contracts to aid mixing of the ingested food.
How many layers of muscle are present in the stomach wall?
Answer: 3
Longitudinal layer - Most superior
Circular layer
Oblique layer - Most inferior
The proton pump is part of the parietal cell.
What is the function of the proton pump with regard to ion exchange across the cell membrane?
A. Chloride into cell, HCO3- out of cell
B. H+ into cell, Chloride out of cell
C. H+ into cell, K+ out of cell
D. HCO3- into cell, Chloride out of cell
E. K+ into cell, H+ out of cell
E. K+ into cell, H+ out of cell
The digestive tract has a rich blood supply.
Which of the following vessels supplies arterial blood to the Jejunum?
A. Direct branches from Aorta
B. Inferior Mesenteric Artery
C. Right Gastro-Epiploic Artery
D. Splenic Artery
E. Superior Mesenteric Artery
E. Superior Mesenteric Artery1
Regarding the embryology of the GI tract.
Which of the following structures is classified in embryology as part of the ‘foregut’?
A. Gallbladder
B. Lower third of oesophagus
C. Pancreas
D. Pancreas, Gallbladder, proximal 2 parts of the duodenum and the lower third of the oesophagus
E. Proximal 2 parts of Duodenum
D. Pancreas, Gallbladder, proximal 2 parts of the duodenum and the lower third of the oesophagus
The stomach contains a variety of cell types.
Which of these substances is secreted by D cells?
A. Adrenaline
B. Gastrin
C. Pepsinogen
D. Somatostatin
E. Stomach acid
D. Somatostatin
A 23 year old patient complains of stomach pains after taking a Non-steroidal anti-inflammatory analgesic (NSAID).
How do NSAIDs irritate the stomach?
A.By decreasing chloride secretion through inhibition of the K/Cl exchange pump
B.By increasing acid secretion through stimulation of the proton pump
C. By increasing secretion of pepsinogen
D.By inhibition of gastrointestinal mucosal cyclo-oxygenase (COX) activity
E.By stimulating the vagus nerve to secrete more acetylcholine
D.By inhibition of gastrointestinal mucosal cyclo-oxygenase (COX) activity
NSAIDs inhibit COX-1 and COX-2 (COX = cyclo-oxygenase).
COX-2 is the target enzyme and blockade of this will inhibit production of inflammatory and nociceptive-enhancing prostaglandins.
Inhibition of COX-1 will prevent production of gastro-protective prostaglandins.
The stomach contains a variety of cell types.
Which of these substances is secreted by G cells?
A. Gastrin
B. Glycogen
C. Pepsinogen
D. Secretin
E. Somatostatin
A. Gastrin
The stomach contains a variety of cell types.
Which of these substances is secreted by Enterochromaffin-like (ECL) Cells?
A. Acetylcholine
B. Amylase
C. Histamine
D. Pepsinogen
E. Somatostatin
C. Histamine
