Digestive System

Factors that may affect the rate of absorption of certain medications with age include

-slowing of the exit of chyme from the stomach. -slowing peristalsis. -thinning of the stomach lining. -slowed secretion of intrinsic factor.

Arrange the ducts in the order that bile would pass through them when moving from the bile canaliculi to the small intestine without being stored in the gallbladder. (1) common bile duct (2) common hepatic duct (3) cystic duct (4) left and right hepatic ducts

4,2,1

This figure shows the stomach. Which number indicates the fundus?

8

One of the major functions of the large intestine is to

absorb ingested water.

The __________ cells of the mucosa have microvilli and produce digestive enzymes and take in digested food.

absorptive

Pernicious anemia develops if there is a vitamin ________ deficiency.

B12

Gastric secretion begins during the ________ phase and ends during the ________ phase.

cephalic ; intestinal

Free amino acids are absorbed into the blood stream by

cotransport with Na+.

Which of the following enzymes is produced by the stomach?

pepsin

Reflux of gastric contents into the esophagus occurs because of

relaxation of the cardiac sphincter.

Carbohydrate digestion begins in the mouth with the secretion of _____________, but most occurs in the duodenum as a result of the secretion of ___________.

salivary amylase, pancreatic amylase

All of the enzymes that digest protein are

secreted in an inactive form.

Acidic solutions in the duodenum cause the release of the hormone __________ that will inhibit gastric secretion.

secretin

When chyme enters the duodenum, ____ is released and stimulates the pancreas to secrete bicarbonates.

secretin

Damage to which of the following nerves would reduce GI secretions?

vagus nerve

Cholesterol produced by the body is transported in the blood as

very low-density.

What structures comprise a portal triad?

Branches of the hepatic artery, hepatic portal vein, and hepatic duct

The submucosa of the duodenum contains coiled, tubular mucous glands called __________, which open into the base of the intestinal glands.

Brunner glands

The disorder of the large intestine producing a "cobblestone" effect within the tissues of the colon is

Crohn's disease.

Churning and mixing movements called segmentation take place only in the

Small intestine

Elliot thought that his peptic ulcers were caused by his nagging parents, and was surprised when the doctor handed him a prescription for medication to treat

a bacterial infection.

Which of the following does not occur during the gastric phase of gastric secretion?

-Gastrin begins to be secreted by the lower part of the stomach. -Hydrochloric acid and pepsin secretion is stimulated in the upper and middle parts of the stomach. -Tactile sensation of food in the mouth sends nervous impulses to the medulla oblongata.

Which of the following are major functions of the liver?

-Storage of certain molecules -Formation of urea -Secretion of bile -Maintaining blood glucose concentration

What is mastication?

Chewing and mixing food with saliva

Match the enzyme with the major food type that it helps to digest.

Chymotrypsin: Proteins Pepsin: Proteins Salivary amylase: Carb Lingual lipase: Lipids Disaccharidases: Carb Gastric lipase: Lipids Carboxypeptidase: Protein Pancreatic lipase: Lipids Trypsin: Proteins Peptidases: Proteins Bile salts: Lipids Pancreatic amylase: Carbs

This figure shows the stomach. What structure does number 3 indicate?

Duodenum

Digestion of starch starts in the stomach.

False

Inhibiting the actions of the parietal cells would stimulate protein digestion.

False

The medulla oblongata controls gastric secretion both by the parasympathetic branch of the nervous system and the endocrine system.

False

When chyme enters the duodenum, gastric secretion increases.

False

Digestion begins in oral cavity and continues in the stomach but most digestion occurs in the distal end of the small intestine, the ileum. Water, ions, and water-soluble digestion products such as glucose and amino acids are transported into the lymphatic capillaries called lacteals. Absorption is the means by which molecules are moved out of the digestive tract into the circulation for distribution throughout the body.

False False True

Match the functions with the correct region:

Ingestion, mastication, and digestion: Oral cavity Breathing, swallowing, and protection: Pharynx Propulsion and protection: Esophagus Storage, digestion, and absorption: Stomach Neutralization, digestion, and excretion: Small intestine Storage, absorption, and elimination: Large Intestine

This figure shows an intestinal villus. The structure indicated by number 1 is a(n)

Lacteal

VLDL are produced in which organ?

Liver

Glucose is absorbed by __________ into the intestinal epithelial cells.

Na+ symport

________stimulation via the ________ nerve causes the secretion of HCl in the stomach.

Parasympathetic ; vagus

Matthew takes a drug that inhibits the production of HCl in the stomach to ease the symptoms of a gastric ulcer. If he takes it for a long time, digestion of which nutrient would be affected the most?

Proteins

Why doesn't the stomach digest itself?

The stomach wall is protected by large amounts of mucus.

Cholecystokinin, a hormone released from intestinal mucosa as a result of stimulation by the presence of fats in the small intestine, stimulates the gallbladder to contract and release bile into the duodenum.

True

Distention of the stomach has a direct stimulatory effect on the gastric glands.

True

Gastrin functions to increase the production of HCl in the stomach.

True

_______ is a protein-splitting enzyme in pancreatic juice.

Trypsin

Gallstones may form if

bile is too concentrated.

The tissues turning yellow (jaundice) is due to the accumulation of

bile pigments.

The taste and smell of food, the stimulation of tactile receptors during the process of chewing and swallowing, and pleasant thoughts of food in the __________ phase of gastric regulation act on centers in the medulla oblongata.

cephalic

Pepsinogen is produced by __________ and is activated by __________, which is secreted by __________.

chief cells; hydrochloric acid (HCl); parietal cells

Shortly after a meal, the gallbladder contracts in response to stimulation by __________.

cholecystokinin

Pancreatic enzymes are secreted in response to a hormone called __________.

cholecystokinin (CCK)

Gallstones are usually composed of

cholesterol.

The __________ ligament attaches the liver to the diaphragm.

coronary

Edith suffers from severe heartburn. She goes to her physician and is diagnosed with a hiatal hernia. This condition affects her

diaphragm

Most protein digestion occurs in the

duodenum and jejunum.

Heartburn is usually caused by the effects of gastric juice on the

esophagus.

Intrinsic factor

facilitates the absorption of vitamin B12.

Inability of the pyloric sphincter to open would prevent

food from entering the small intestine.

The hormone ______ stimulates secretion of _______ in the stomach.

gastrin ; pepsin

The bile ducts of the liver unite to form the

hepatic ducts.

The parietal cells of gastric glands secrete

hydrochloric acid

Secretin is released from the duodenum in response to

hydrochloric acid in chyme.

Vitamin B12 is primarily absorbed in the

ileum

Which structure is highlighted?

laryngopharynx

Lipid digestion and absorption requires the coordinated actions of ______ and ____.

lipase, bile.

Strong peristaltic contractions in the large intestine are called

mass movements.

Which of the following motility processes is NOT correctly matched to its description?

mastication - removal of wastes

What is the purpose of segmental contractions of the small intestine?

mixing of intestinal contents

Damage to which tunic of the GI tract would directly affect Auerbach's plexus?

muscularis

The mesentery connecting the lesser curvature of the stomach and the proximal end of the duodenum to the liver and diaphragm is called the lesser __________.

omentum

It is good that Emily does not remember being a newborn, because she was miserable, vomiting very often. An X-ray reveale hypertrophic pyloric stenosis. The problem in Emily's digestive system, before surgery helped her, was

overgrowth of muscle that blocked the pyloric canal.

Which structure is highlighted?

pancreas

Which of the following organs is retroperitoneal?

pancreas ascending colon duodenum descending colon

Hydrochloric acid (HCl) is secreted by __________ cells.

parietal

Bile secretion is

performed continuously by the liver.

Wavelike muscular contraction of the gastrointestinal tract is called

peristalsis

The serous membrane that covers organs in the abdomen is the visceral __________.

peritoneum

Functions of the liver include

production of many blood proteins. -interconversion of nutrients. -detoxification of harmful chemicals. -bile production.

Secretion of cholecystokinin from the intestinal wall is stimulated by

protein and fat in the small intestine.

Which of the following pairs is mismatched?

pulp cavity - cementum

Which structure is highlighted?

pyloric sphincter

Which of the following does NOT stimulate the secretion of HCl in the stomach?

secretin

Amino acids and monosaccharides are absorbed in the __________, and fatty acids are absorbed in the __________.

small intestine; small intestine

The hormone secretin

stimulates release of pancreatic juice.

What is the function of the gallbladder?

store and concentrate bile

The acidic chyme entering the duodenum initiates all of the following actions EXCEPT:

the intestinal phase of gastric function

Which of the following enzymes is mismatched with its substrate?

trypsin - nucleic acids

Tiny fingerlike projections of the mucosa of the small intestine that help to increase surface area are known as __________.

villi

The arrival of chyme into the duodenum begins the _______ phase of stomach function.

Intestinal

The enzymes for digestion of carbohydrates come from all of the following EXCEPT the

Liver

Match the cells with the secretion they produce:

Parietal cells: Hydrochloric acid Chief cells: Pepsinogen Endocrine cells: Endocrine cells: Histamine Parietal cells: Intrinsic factor Neck cells: Mucous

Which of the following enzymes functions at the lowest pH?

Pepsin

Helicobacter pylori is a bacterium associated with

Peptic Ulcers

Lymphatic nodules called __________ are numerous in the mucosa and submucosa of the ileum and initiate immune responses against microorganisms that enter with food.

Peyer patches

True or False: Each action listed here is a major function of the liver.

Production of bile True Glycogen storage True Interconversion of nutrients True Filtering the blood False Detoxification True Phagocytosis True Bile storage False Production of digestive enzymes False

Pancreatic acinar cells secrete pancreatic juice.

True

Secretin is released from the duodenum in response to acidic chyme.

True

Match the pancreatic secretion with the correct function:

Trypsin: Digests proteins Chymotrypsin: Digests proteins Carboxypeptidase: Digests proteins Pancreatic amylase: Digests carbohydrates Pancreatic lipase: Digests lipids Ribonuclease: Digests RNA Deoxyribonuclease: Digests DNA Bicarbonate ions: Neutralizes acid