Question 1

Which layer of the alimentary canal is primarily responsible for absorption of nutrients and protection against infectious disease?

Accepted Answer

Mucosa

Question 2

During carbohydrate digestion, which enzyme is responsible for breaking down starch in the mouth?

Accepted Answer

Salivary amylase

Question 3

Which accessory digestive organ produces bile, a substance essential for fat emulsification?

Accepted Answer

Liver

Question 4

What is the primary function of the gallbladder?

Accepted Answer

Storage and concentration of bile

Question 5

Which of the following best describes the process of peristalsis in the GI tract?

Accepted Answer

Rhythmic contraction of smooth muscle to propel food forward

Question 6

Which hormone stimulates contraction of the gallbladder and release of bile into the duodenum?

Accepted Answer

Cholecystokinin (CCK)

Question 7

In protein digestion, which enzyme is secreted in an inactive form and activated in the duodenum?

Accepted Answer

Trypsinogen

Question 8

Which structure increases the surface area for absorption in the small intestine?

Accepted Answer

Villi

Question 9

What is the correct equation for the formation of hydrochloric acid (HCl) in the stomach?

Accepted Answer

$$\mathrm{CO_2$ + H_2O \rightarrow H_2CO_3 \rightarrow H^+ + $$HCO_3$$^-}$$

Question 10

Which of the following is absorbed directly into the capillary blood in villi after lipid digestion?

Accepted Answer

Glycerol and short chain fatty acids

Question 11

A patient with pernicious anemia is most likely lacking which stomach secretion?

Accepted Answer

Intrinsic factor

Question 12

Which process is responsible for the movement of water from the GI tract into the bloodstream?

Accepted Answer

Osmosis

Question 13

Which of the following is a function of the bacterial flora in the large intestine?

Accepted Answer

Synthesis of vitamin K and B vitamins

Question 14

Which reflex is initiated by the presence of food in the stomach and results in mass movements in the colon?

Accepted Answer

Gastrocolic reflex

Question 15

Which vitamin requires intrinsic factor for absorption in the small intestine?

Accepted Answer

Vitamin B12

Question 16

Which of the following best describes the absorption of glucose in the small intestine?

Accepted Answer

Secondary active transport with Na+

Question 17

If the ileocecal valve fails to close properly, which of the following is most likely to occur?

Accepted Answer

Regurgitation of chyme into the ileum

Question 18

Which equation represents the activation of trypsinogen to trypsin in the duodenum?

Accepted Answer

$$\mathrm{Trypsinogen + Enteropeptidase \rightarrow Trypsin}$$

Question 19

Which of the following is a consequence of high cholesterol and too few bile salts in the gallbladder?

Accepted Answer

Gallstones (biliary calculi)

Question 20

Which process is primarily responsible for the propulsion of feces toward the anus in the large intestine?

Accepted Answer

Mass movements

Digestive System: Structure, Function, and Processes

Study Guide - Practice Questions