Digestive System Quiz

Gastric secretions are stimulated by ___ and are inhibited by ___.

• acid chyme in the duodenum; gastrin

• secretin; chymotrypsin

• gastrin; secretin

• cholecystokinin; somatomedin

Most nutrient absorption occurs in the __. If the thoracic duct were to be tied off, which class of nutrients would NOT enter the circulation at their normal rate?

• stomach and esophagus; glucose

• duodenum and jejunum; lipids

• ileum and cecum; amino acids

• hepatic-portal system; lactose

Salivary gland secretion is primarily controlled by the __ and the components of saliva include all of the following EXCEPT __.

• vagus nerve; lysozyme

• facial and glossopharyngeal nerves; immunoglobulin E (IgE)

• taste centers of the medulla; immunoglobulin A (IgA)

• olfactory nerves and hypoglossal nerves; mucin

Which of the following stomach cell types is correctly matched with its function?

• mucous cells — produce intrinsic factor

• parietal cells — produce pepsinogen

• chief cells — produce HCl

• endocrine cells — produce gastrin

When part of the stomach extends through the diaphragm into the thoracic cavity, the condition is known as

• esophagitis

• an ulcer

• a hiatal hernia

• pyloric stenosis

Reflux of the gastric contents into the esophagus occurs because of

• relaxation of the cardiac sphincter

• contraction of the pyloric sphincter

• spasms of the submucosal layer of the stomach wall

• increased hydrochloric acid production by the parietal cells

The cephalic phase of gastric secretion

• decreases the release of gastrin on the stomach

• is triggered by taste, thought, smell or food

• is mediated by impulse on sympathetic nerves

• leads to the greatest volume of gastric secretion

The enterogastric reflex can be triggered by

• distension of the duodenal wall

• the presence of irritating substances in the duodenum

• increased pH in the duodenum

• both A and B

Gastrocolic reflexes are reflexes that

• empty the stomach

• release gastric secretions into the stomach

• cause mass movements of the colon when food is present in the stomach

• lead to mass movements of the colon in response to food in the duodenum

The defecation reflex

• is stimulated by distention of the rectum

• inhibits further peristalsis in the rectum and lower colon

• constricts the internal anal sphincter

• lasts several hours