Question

Question 16

HCO3- is secreted from pancreatic cells into the pancreatic duct by which of the following apical membrane transporters?

HCO3-/Cl- antiport

HCO3-/Cl- ATP ase pump

HCO3-/H+ antiport

Question 17

All of the following occur during the Intestinal Phase of digestion EXCEPT:

Gastric motility increases

The secretion of Secretin raises intestinal pH.

The secretion of Cholecystokinin ensures micelle formation

Insulin is released from Beta cells of the pancreas

Question 18

Which of the following describes the interaction between extrinsic neurons and the enteric nervous system?

GI distention stimulates sensory afferent vagus neurons which synapse with the vagus motor neurons that connect to motor neurons of the enteric nervous system

GI distention and chemoreceptors stimulate sensory afferent vagus neurons which synapse with the motor neurons of the myenteric plexus

GI distention stimulates sensory afferent vagus neurons which synapse with the enteric nervous system causing peristalsis

GI distention stimulates sensory afferent vagus neurons which release Acetylcholine causing contraction of the muscularis externa

Question 19

Which of the following describes the action of a proton pump inhibitor such as Omeprazole?

It blocks the H+/K+ ATPase pump on the apical membrane of the parietal cell

It blocks the binding of Histamine to its H2 receptor on the basolateral side of the parietal cell

It blocks the steps of signal transduction involved in inserting H+/K+ ATPase pumps into the apical membrane of the parietal cell

It blocks the release of Histamine from Enterchromaffin-like cells

Question 20

Which of the following is co-transported with Na+ on the apical membrane of the small intestines?

Amino acids

Di and tripeptides

Fructose

Micelles

Peptides

Question 21

Someone with an obstruction of the common bile duct may exhibit which of the following?

An increase in blood levels of conjugated bilirubin resulting in jaundice

An increase in unconjugated bilirubin in the blood resulting in jaundice

Alcoholic fatty acid liver disease

Increased enterohepatic circulation of bilirubin

Increased excretion of urobilinogen

Question 22

Steatorrhea with macrocytic anemia may be caused by which of the following?

A resected ilium

A common bile duct obstruction

Fatty liver disease

Hepatitis

Answer 1

16. HCO3-/H+ antiport

Bicarbonate and digestive enzyme secretion occurs from the pancreatic cells and drained into pancreatic duct, this is required for the buffering of the chyme entering into small intestine and activatation of enzymes.The cells of pancreatic duct epithelium contains the HCO3-/H+ transporters which is mediated via the H+-K+ ATPases and Na+- K+ ATPases.

17.Gastric motility increases

The intestinal phase starts when chyme enters into the small intestine through duodenum, it reduces the gastric motility and secretion via enterogastric reflexes, thus reduces the vagal stimulation of stomach via sympathetic neuron signal inhibition. During this period chyme acts upon the enteroendocrine cells to release the secretin and cholecystokinin hormones ,these hormones acts upon pancreas, gallbladders and triggers the release of insulin and bile .

18.GI distention stimulates sensory afferent vagus neurons which synapse with the enteric nervous system causing peristalsis

The sensory vagus neurons sesne the nutreints at the proximal ,distal intestine and hepatic portal system.GI distention stimulates the sympathetic activity in turn activates the splanchnic nerve and GI motility through peristalsis.This activity causes the sensory afferent vagus neurons to establish  synapse with the vagus motor neurons present in the brain stem.

19.It blocks the H+/K+ ATPase pump on the apical membrane of the parietal cell

The proton pump inhibitor causes the the reduces of gastroesophageal reflux by inhibition of gastric enzyme secretion.The protopn pump inhibitor omeprazole inhibits the H+/K+ ATPase system occuring at the apical surface of the parietal cells of stomach lining, thus reduces the gastric secretion.

20.Fructose

In the upper section of small intestine, the sodium and glucose (fructose) are coupled transported through the brush border membrane of enterocyte of the small intestine via the transporter named as Na+/glucose cotransporter SGLT1.

21.An increase in blood levels of conjugated bilirubin resulting in jaundice

Obstruction of the common bile duct causes the blocage of bile from the liver to intestine via gall bladder, thus the bile starts building up into the liver and increases bilirubin level in blood (conjugating bilirubin) results into jaundice.

21.A resected ilium

Steatorrhea with macrocytic anemia arises due to the malabsorption of fat which may occur in the ilium region of the which is resected.The resected ilium may unable to cause the stimulation of pancreatic lipase and bile from the liver which causes the inhibition of emulsification of fat and absorption of fatty acid through small intestine.