Chapter 2, Problem 1SC

Which of the following is true regarding digestion?   A. The first segment of the alimentary tract is the duodenum.   B. Amylase hydrolyzes starches into simple sugars.   C. Bile hydrolyzes amylase into simple sugars.   D. Trypsin and chymotrypsin degrade lipids into free fatty acids.   E. All of the above answer choices correctly answer the question.

Which of the following is an unregulated process in the digestive tract? a. secretion of cholecystokinin (CCK) by the duodenal mucosa b. absorption of amino acids across the epithelium of the small intestine c. release of bicarbonate ion (HCO3–) by pancreatic duct cells d. peristalsis in the stomach

Peristalsis: A. Responsible for propelling food in the esophagus B. Represents the contractions of smooth muscles lining the GIT innervated by the myenteric plexus C. Responsible when the vagus nerve detects chemical composition of food D. A and BE. All of the above

The region of the digestive tract most responsible for absorption of nutrients is the: a. stomach b. small intestine c. large intestine d. liver

A. What is/are the primary role(s) of the large intestine? a. to complete enzymatic digestion and store indigestible material b. to initiate enzymatic digestion of carbohydrates and to store water c. to absorb water from digested material, with essentially no digestive role of its own d. to secrete water into the material that is left over after all available nutrients have been absorbed e. to digest fats A. In the intestine most nutrients are absorbed regardless of whether the body has an immediate need or shortfall of them; ie there is little control over amounts taken up – which of the following does not follow this rule? a. absorption of sodium b. absorption of water c.absorption of iron d. absorption of fat soluble vitamins e. none of the above follow this rule – close control is exerted over all of them

The release of CCK and bile is triggered when fat enters the Select one: a. small intestine Ob. esophagus stomach C. O d. d. mouth Oe. large intestine

The normal mechanism of defecation involves:A. Stretch receptors located in the duodenum and jejunum initiate a long-lasting reflex that relaxes the internal anal sphincter several hours after food initially passes from the stomach to the intestines.B. Stretch receptors located in the rectal wall initiate the defecation reflex inresponse to an incoming mass movement.C. The defecation reflex involves contraction of the rectal wall and simultaneous relaxation of the internal anal sphincter.D. Digestive fluids secreted from the pancreas and gall bladder contain enzymesthat act on the smooth muscle of the intestine, stimulating peristalsis.E. Conscious signals from the cortex will allow for relaxation of the external anal sphincter (when appropriate!).

The pyloric sphincter connects the: a. Esophagus and stomach b. Stomach and small intestine c. Stomach and large intestine d. Small intestine and large intestine

Select the letter of the choice that best completes the statement. Food is absorbed in the small intestine in thea. villi.b. submucosa.c. peritoneal lining.d. colon.