-
Question 1
Incorrect
-
Which three parietal cell agonists bind at the basolateral membrane at specific receptors respectively: M3 , H2 , CCK-B, to stimulate acid secretion?
Your Answer: Histamine, acetylcholine, gastrin
Correct Answer: Acetylcholine, histamine , gastrin
Explanation:The three agonists of parietal cell secretion are gastrin, acetylcholine and histamine. Parietal cells are responsible for the secretion of HCl and intrinsic factor.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 2
Correct
-
In paralytic ileus the following are true except:
Your Answer: Opioid blocking drugs will exacerbate the symptoms
Explanation:Paralytic ileus causes adynamic intestinal obstruction or decreased peristalsis and the most common reason being postoperative ileus. Opioid drugs like morphine are given for pain management and cause decreased peristalsis in the gut resulting in constipation. Theoretically opioid blocking drugs or opioid antagonists can increase peristalsis and can alleviate paralytic ileus symptoms.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 3
Correct
-
VIP, GIP and somatostatin play an inhibitory role in gastric acid secretion by inactivating?
Your Answer: G cells
Explanation:Gastrin is secreted from the G cells. VIP, GIP and somatostatin all inhibit acid production by inhibiting the G cells.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 4
Correct
-
Which of the following can trigger parietal cell secretion?
Your Answer: Gastrin
Explanation:The three agonists of parietal cell secretion are gastrin, acetylcholine and histamine. Parietal cells are responsible for the secretion of HCl and intrinsic factor.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 5
Correct
-
In the gastric mucosa, which of the following cells is known to secrete gastric lipase?
Your Answer: Chief cell
Explanation:Chief cells produce pepsinogen and gastric lipase. Parietal cells produce stomach acid and intrinsic factor.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 6
Correct
-
The pressure in the sinusoids is normally:
Your Answer: Lower than portal venous pressure
Explanation:The direction of transport of nutrients in the portal vein occurs from the portal vein to the hepatic sinusoids. Thus, he pressure of sinusoids should be lower than the pressure of he portal vein.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 7
Incorrect
-
The ATPase of parietal cells moves:
Your Answer: H+ from the gastric lumen in exchange for a K+
Correct Answer: H+ into the gastric lumen in exchange for a k+
Explanation:ATPase of the parietal cell is also known as the proton pump, which moves H+ ions into the gastric lumen in exchange for K+ ions into the cell.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 8
Correct
-
How are the long chain fatty acids (more than 10 to 12 carbon atoms) absorbed?
Your Answer: Re-esterified to triglycerides and enter the lymphatics as chylomicrons
Explanation:Short and medium chain fatty acids are absorbed into the blood via intestinal capillaries and travel through the portal vein. Long chain fatty acids are not directly released into the intestinal capillaries. They are re-esterified to triglycerides and are coated with cholesterol and protein, forming chylomicrons. Chylomicrons are released in the lymphatic system.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 9
Correct
-
Where in the gastrointestinal tract are Brunner glands?
Your Answer: Duodenum
Explanation:Brunner’s glands (or duodenal glands) are compound tubular submucosal glands found in that portion of the duodenum which is above the hepatopancreatic sphincter (aka sphincter of Oddi). The main function of these glands is to produce a mucus-rich alkaline secretion (containing bicarbonate) in order to:- protect the duodenum from the acidic content of chyme (which is introduced into the duodenum from the stomach);- provide an alkaline condition for the intestinal enzymes to be active, thus enabling absorption to take place; lubricate the intestinal walls.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 10
Incorrect
-
Histamine, acetylcholine and gastrin act by way of which second messengers in the release of acid by parietal cells:
Your Answer: Ip3
Correct Answer: A and D
Explanation:Acetylcholine, Histamine and Gastrin receptors are located on the basolateral membrane of the parietal cell and control its activity. Stimulation of these receptors modulates the levels of protein kinases in the cell and brings about the changes from a resting to stimulated structure. Protein kinase catalyses conversion of ATP to cyclic AMP which activates the proton pump. Calcium ions increase gastric acid secretion elicited by gastrin released through a vagal mechanism, and also by a direct effect on parietal cells.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 11
Correct
-
Cholesterol is synthesized in all of these organs EXCEPT?
Your Answer: Stomach
Explanation:The liver primarily synthesizes about 20-25% of the total daily cholesterol. Cholesterol is also synthesized to smaller extents in the adrenal glands, reproductive organs (as cholesterol is the precursor of sex hormones), skin and is also produced in the intestines.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 12
Correct
-
Which of the following is NOT a component of bile?
Your Answer: Unconjugated bilirubin
Explanation:The composition of gallbladder bile is 97% water, 0.7% bile salts, 0.2% bilirubin, 0.51% fats (cholesterol, fatty acids and lecithin), and 200 meq/l inorganic salts (electrolytes).
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 13
Correct
-
The end product of trehalase action on oligosaccharides is
Your Answer: Two glucose molecules
Explanation:Disaccharides are glycoside hydrolases, enzymes that break down certain types of sugars called disaccharides into simpler sugars called monosaccharides.Examples of disaccharides:Lactase (breaks down lactose into glucose and galactose)Maltase (breaks down maltose into 2 glucoses)Sucrase (breaks down sucrose into glucose and fructose)Trehalase (breaks down trehalose into 2 glucoses)
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 14
Correct
-
Which of the following acts on the pancreas to secrete pancreatic juice that is rich in enzymes?
Your Answer: CCK
Explanation:CCK (Cholecystokinin): CCK is released by the duodenum in response to the presence of fats and proteins in the small intestine. It stimulates the pancreas to secrete enzyme-rich pancreatic juice, which aids in the digestion of fats, proteins, and carbohydrates. It also stimulates the gallbladder to contract and release bile.
Secretin: Secretin is released by the duodenum in response to acidic chyme entering from the stomach. It primarily stimulates the pancreas to release bicarbonate-rich pancreatic juice to neutralize the acid, but it does not primarily stimulate enzyme secretion.
Gastrin: Gastrin is produced by G-cells in the stomach. It stimulates gastric acid secretion by the stomach, not pancreatic enzyme secretion.
Chymotrypsin: Chymotrypsin is an enzyme produced by the pancreas. It does not act to stimulate the pancreas; rather, it is a component of the pancreatic juice that helps digest proteins.
Elastase: Elastase is also an enzyme produced by the pancreas. Like chymotrypsin, it is involved in the digestion of proteins and does not stimulate the pancreas.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 15
Correct
-
The parasympathetic innervation of the parotid salivary gland arrives from the salivary nuclei:
Your Answer: CN IX
Explanation:Parasympathetic presynaptic nerve fibers from the glossopharyngeal nerve (CN IX) synapse in the otic ganglion and the postsynaptic parasympathetic nerve fibers pass to the parotid gland via the auriculotemporal nerve.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 16
Correct
-
Bile contains:
Your Answer: Bile acids, phosphatidylcholine, cholesterol
Explanation:The main components of bile include bile acids or bile salts, phospholipids; mainly phosphatidylcholine, cholesterol, bilirubin, inorganic salts; potassium, sodium and bicarbonate.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 17
Correct
-
Which of the following statements correctly describes a function of the parasympathetic innervation of the GI tract.
Your Answer: Parasympathetic cholinergic activity increases the activity of intestinal smooth muscle
Explanation:The parasympathetic nerves stimulate peristalsis and relax the sphincters; they also stimulate secretion. Acetylcholine is the neurotransmitter of the parasympathetic system.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 18
Incorrect
-
In addition to its role in digestion and absorption of fats, bile:
Your Answer: Causes jaundice in hepatitis patients
Correct Answer: Is the major excretory route for lipid-soluble waste products
Explanation:The end product of haem metabolism is bilirubin and jaundice is caused by increased bilirubin levels in the blood. Gallstones are mainly caused by cholesterol and bile pigments. Bile is the main route of excretion for lipid soluble waste products whereas urine is the main route of excretion of water soluble waste products.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 19
Correct
-
Pancreatic juice is usually?
Your Answer: Alkaline
Explanation:Pancreatic juice is alkaline in nature and has a high amount of bicarbonate ions. About 1500 ml is secreted every day. It also contains a large quantity of enzymes in the inactive form.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 20
Correct
-
Which of the following factors is not completely produced in the liver?
Your Answer: Factor viii
Explanation:Factor VIII is produced in liver sinusoidal cells and endothelial cells outside of the liver throughout the body. This protein circulates in the bloodstream in an inactive form, bound to another molecule called von Willebrand factor, until an injury that damages blood vessels occurs.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 21
Correct
-
Colipase is secreted in an inactive form. Its activation in the intestinal lumen is by
Your Answer: Trypsin
Explanation:The enzyme trypsin exists in pancreatic juice in the inactive form trypsinogen, it is activated by the intestinal enterokinase in intestinal juice. Trypsin can then activate other protease enzymes and catalyse the reaction pro-colipase → colipase. Colipase is necessary, along with bile salts, to enable lipase function.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 22
Correct
-
Which of the following is responsible for transporting both glucose and fructose into the interstitium?
Your Answer: GLUT 2
Explanation:Absorption of glucose involves transport from the intestinal lumen, across the epithelium and into blood. The transporter that carries glucose and galactose into the enterocyte is the sodium-dependent hexose transporter, known as SGLT1. As the name indicates, this molecule transports both glucose and sodium ions into the cell. Once absorbed into the enterocyte, glucose must be exported from the cell into blood. Sodium is rapidly shuttled out in exchange for potassium by Na+/K+ ATPase pumps on the basolateral membrane, and that process maintains the electrochemical gradient across the epithelium. Glucose, galactose and fructose are transported out of the enterocyte into the interstitium and in turn into the blood through another hexose transporter (called GLUT-2) in the basolateral membrane. These monosaccharides then diffuse down a concentration gradient into capillary blood.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 23
Correct
-
The channel that coalesces the small pancreatic duct radicles before joining the common bile duct is known as the:
Your Answer: Duct of Wirsung
Explanation:The small ducts from the pancreas coalesce into a single duct known as the pancreatic duct or the duct of Wirsung. It usually joins the bile duct at the ampulla of Vater before entering the duodenum.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 24
Incorrect
-
Regarding carbohydrates absorption;
Your Answer: Intestinal glucose absorption requires phosphorylation
Correct Answer: Intestinal absorption of sugars is inhibited by the drug phlorizin
Explanation:The main role of insulin is in the uptake of glucose from blood to tissues where it is metabolised. Glycose transporters in the intestines do not depend on the action of insulin. Phlorizin is a competitive inhibitor of SGLT1 and SGLT2 because it competes with glucose for the binding site, reducing intestinal and renal glucose transport.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 25
Correct
-
The oligosaccharidases responsible for further digestion of starch after breakdown by the above mentioned enzymes is located where?
Your Answer: Brush border of small intestine
Explanation:The final step in digestion of carbohydrates, which is conversion of disaccharides to absorbable monosaccharides occurs on the small intestinal epithelial cells. The enzymes responsible for this final stage of digestion are not freely found in the intestinal lumen, but they are found as integral membrane proteins in the plasma membrane of the epithelial cell. The apical plasma membrane of the intestinal epithelial cell has numerous microvilli known as the brush border. Thus, the enzymes embedded in those microvilli are referred to as brush border enzymes.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 26
Correct
-
Cholinergic neurons that pass into a retrograde direction activate neurons that release:
Your Answer: Substance P and acetyl choline
Explanation:Serotonin activates sensory neurons that activate the myenteric plexus. Cholinergic neurons passing in a retrograde direction in the myenteric plexus activate neurons that release substance P and acetylcholine, causing smooth muscle contraction.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 27
Correct
-
With regard to carbohydrate absorption, which sodium-dependent glucose transporter (SGLT) is responsible for the uptake of dietary glucose from the gut?
Your Answer: SGLT 1
Explanation:SGLT- Sodium-dependent glucose cotransporter or sodium-glucose linked transporter are family of proteins of different types. SGLT1 transporter is found in the intestinal mucosa of the small intestine.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 28
Correct
-
What percentage of blood to the liver is supplied by hepatic artery?
Your Answer: 25%
Explanation:The liver receives a dual blood supply from the hepatic portal vein and hepatic arteries. The hepatic portal vein delivers approximately 75% of the liver’s blood supply, and carries venous blood drained from the spleen, gastrointestinal tract, and its associated organs. The hepatic arteries supply arterial blood to the liver, accounting for the remaining quarter of its blood flow.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 29
Incorrect
-
Which of the following would provide relief from nausea and vomiting?
Your Answer: Bromocriptine
Correct Answer: Cannabinoids
Explanation:Ondansetron, chlorpromazine and haloperidol are effective antiemetic agents. Corticosteroids, cannabinoids, and benzodiazepines, alone or in combination with 5-HT3 and D2 antagonists, are also useful in the treatment of vomiting produced by chemotherapy.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
-
Question 30
Incorrect
-
Anti-gastroesophageal reflux mechanisms include the following except:
Your Answer: The phrenoesophageal ligament
Correct Answer: Peristaltic movements of the oesophagus
Explanation:The lower oesophageal sphincter contracts preventing reflux of acid into the oesophagus. The sling muscles of the stomach, the crura of the diaphragm and the phreno-oesophageal ligament all play an important role in constricting the lower portion of the oesophagus and preventing reflux. Peristaltic movements do not stop the acid reflux.
-
This question is part of the following fields:
- Gastrointestinal
- Medicine
-
SESSION STATS - PERFORMANCE PER SPECIALTY
