Sample Questions 2

Question 1

The initial force that is responsible for the generation of fluid movement by GI exocrine epithelial tissues is:

Answer 1

gravity

Question 2

The GI tract is responsible for

Answer 2

• providing the body with all of the nutrients required for their metabolism
• digesting all of the foodstuff to end products suitable for absorption
• elimination of non-digestible dietary constituents

Question 3

The total volume of exocrine secretions into the GI tract during a normal day in humans is:

Answer 3

more than 5 liters

Question 4

The single largest component in feces by weight is:

Answer 4

water

Question 5

There is ample transport capacity into the small intestine for the absorption of all salts and dietary solutes in a normal meal. True or false.

Answer 5

true

Question 6

What causes the pyloric sphincter to relax:

Answer 6

gastrin

Question 7

When parietal cells are actively secreting acid a H+ ion is exported across the apical membrane on a carrier…

Answer 7

in exchange for a K+ ion

Question 8

What inhibits parietal cell acid secretion?

Answer 8

histamine

Question 9

Stimulation of the vagus nerve

Answer 9

• Causes gastrin release from endocrine cells in the gastric antrum
• causes relaxation of the smooth muscle comprising the pyloric sphincter, thus allowing it to open

Question 10

The duodenum influences the rate of gastric acid secretion by:

Answer 10

• operating through the ENS to inhibit parietal cell secretion when the walls of the duodenum are distended by excess volume
• releasing a hormone in response to luminal acidity which operates back upon the stomach to inhibit parietal cell acid secretion directly
• releasing a hormone in response to amino acids in the luminal chyme which reduces gastric acid secretion and the strength of gastric peristaltic contractions

Question 11

A hormone which stimulates parietal cell acid secretion also stimulates increased gastric emptying; a hormone which reduces parietal cell acid secretion also reduces gastric emptying. True or false?

Answer 11

True

Question 12

The mucus gel on the surface of the gastric and duodenal mucosa :

Answer 12

• serves to slow the diffusion of gastric pepsin to the mucosal cell surface
• is the zone where protons are neutralized by HCO3
• is the zone where gastric pepsin is inactivated by the high pH

Question 13

When a peristaltic contraction into the gastric antrum reaches the pyloric sphincter, the sphincter relaxes. True or false?

Answer 13

false

Question 14

When the gastric antral contractions become stronger it is because they are occurring more frequently. True or false.

Answer 14

false

Question 15

When gastric antral smooth muscle is becoming more excitable the smooth muscle membrane potential is hyperpolarizing and moving away from the theshold potential. True or false

Answer 15

false

Question 16

The relaxation of the smooth muscle in the wall of the stomach as it fills:

Answer 16

allows the stomach to accommodate the meal without increasing intragastric pressure

Question 17

To digest and absorb the contents of a large meal requires about ___ hours.

Answer 17

8

Question 18

When a new meal is ingested, these events occur:

Answer 18

• the ileum contracts
• the slow peristaltic type of contraction occurring over the length of the small intestine ceases
• a colonic mass movement becomes more likely

Question 19

When a new meal is ingested, the gastric antral smooth muscle becomes less excitable. True or false.

Answer 19

false, more

Question 20

The meal that is likely to empty slowly from the stomach is one of:

Answer 20

high alkalinity

Question 21

function of cholecystokinin includes

Answer 21

• release of pepsin and lipase from chief cells of the stomach
• contract the gallbladder
• reduces gastric peristaltic contractions
• relaxes the sphincter of Oddi

Question 22

Highly acidic chyme in the lumen of the stomach or small intestine may ______ somatostatin secretion

Answer 22

stimulate