Unit 7: Digestive System

The ________ are pointed teeth that are adapted for tearing and slashing.

Cuspids

True or False: About one-third of the food reaching the stomach is digested and absorbed into the blood before leaving the stomach.

False

True or False: Eliminating waste products is the most important function of the gastrointestinal tract.

False

Which of the following is true concerning pepsinogen? It acts directly to initiate the catabolism of proteins. It is secreted by the pancreas and activated in the small intestine. It reacts with gastrin to yield pepsin. - It reacts with HCl to yield pepsin.

It reacts with HCl to yield pepsin.

The ________ are teeth with flattened crowns and prominent ridges that are adapted for crushing and grinding.

Molars

Gastrin is:

a hormone which stimulates secretion of HCl by the parietal cells

The carbohydrate in a coke would most likely be digested by which of the following?

amylase

Pepsin

an enzyme found in gastric juice involved in breaking down proteins

Lipase

an enzyme found in pancreatic juice involved in breaking down fat

Trypsin

an enzyme found in pancreatic juice involved in breaking down proteins

Amylase

an enzyme secreted by the salivary glands

Accumulation of fluid in the peritoneal cavity is termed

ascites

The roof of the oral cavity is formed by

both the hard palate and the soft palate

Which of the following is NOT a major function of the digestive system? disposing wastes breaking polymers into monomers absorbing nutrients building complex organic molecules

building complex organic molecules

The esophagus connects to which region of the stomach?

cardia

Pepsin:

catabolizes proteins

Which of the following descriptions best matches the term cholecystokinin (CCK)?

causes gall bladder to contract

The presence of fat in the duodenum:

causes the release of cholecystokinin

The appendix is most closely associated with which of the following structures?

cecum

The muscularis layer of the gastrointestinal tract is:

contains both circular and longitudinal smooth muscle fibers

A sphincter:

controls openings to some digestive system organs

Hydrochloric acid in the stomach:

converts pepsinogen into active pepsin

The functions of the oral cavity include all of the following except a) analysis of material before swallowing. b) mechanical processing of food. c) lubrication. d) absorption of monosaccharides. e) digestion of carbohydrates.

d) absorption of monosaccharides

A disease that attacks and disables the myenteric plexus would

decrease intestinal motility

The bulk of each tooth consists of a mineralized matrix similar to that of bone called

dentin

Most of the digestion of food occurs in the:

duodenum and jejunum

The crown of a tooth is covered by

enamel

Which of the following is not a direct function of the digestive tract? -secretion -digestion -absorption -energy production

energy production

The gastric phase of gastric secretion is triggered by the

entry of food into the stomach.

All of the following are composed of smooth muscle except: pyloric sphincter internal anal sphincter external sphincter ileocecal valve

external sphincter

True or False: All movements of the gastrointestinal tract are initiated by nerve impulses originating in the spinal cord or higher brain centers.

false

True or False: Swallowing is controlled by gravity. Therefore one cannot swallow when standing on one's head.

false

Blockage of the common hepatic duct would interfere with digestion of

fats

The digested products of which of the following substances is absorbed primarily into lymphatic capillaries in the villi?

fats

Which of the following molecules are absorbed in the small intestine?

fatty acids, monosaccharides, and amino acids

When it is heated, Benedict's solution will change:

from blue to colors ranging from green to red if disaccharides are present

An abnormality in one of the following organs can lead to crystallization of cholesterol compounds which can obstruct ducts. Removal of this organ does not appear to interfere seriously with the patient. This organ is the:

gallbladder

The material which causes fat to emulsify is stored in the:

gallbladder

G cells of the stomach secrete

gastrin

Your patient has inflammation of the mucous membrane lining of the stomach. This is known clinically as

gastritis

A patient is observed to have inflamed and bleeding gums. This condition is called:

gingivitis

Secretin and cholecystokinin are:

hormones secreted by the duodenum

Parietal cells secrete

hydrochloric acid

Gastric ulcers may be caused by:

hypersecretion of HCl

The portion of the small intestine that attaches to the cecum is the

ileum

The presence of chyme in the duodenum may stimulate secretin which then functions to:

initiate the secretions of pancreatic juice rich in bicarbonate

Constipation is a condition:

involving increased water absorption from the large intestine

The large intestine:

is important in the absorption of water and some vitamins

Pepsinogen:

is produced by the chief cells of the gastric mucosa

Which of the following is not true of bile? it is formed by the liver it is stored in the gallbladder in concentrated form it contains enzymes important in the digestion of fat it contains a number of waste products including the breakdown products of hemoglobin

it contains enzymes important in the digestion of fat

Products of fat digestion are transported initially by

lacteals

The organ that functions primarily to absorb water and some vitamins is:

large intestine

The fat in a peanut butter sandwich would be digested by which enzyme below?

lipase

Fats are digested by:

lipase secreted by the pancreas

Bile is produced in the:

liver

Bile is secreted from the ____________ and stored in the ___________.

liver, gallbladder

The taeniae coli are

longitudinal bands of smooth muscle on the outer surface of the colon

Bile salts assist in the digestion of fats by:

making fat globules fragmented (emulsified) so they can more readily be digested by lipase

Which structure functions to prevent the small intestines from becoming twisted?

mesentery

Which types of digestion products are absorbed into blood-containing capillaries of the small intestines?

monosaccharides and amino acids

The layer of the gastrointestinal tract in direct contact with food or chyme is the:

mucosa

A viral infection that often involves the parotid glands, which swell noticeably, is

mumps

Which duct from the salivary glands does not open into the mouth adjacent to the lingual frenulum (under the front of the tongue)? -parotid duct -they all open under the front of the tongue. -submandibular duct -sublingual duct

parotid duct

Chyme is:

partially digested food mixed with secretions found in the stomach or intestine

which are enzymes important in the digestion of protein?

pepsin, trypsin, and chymotrypsin

Which of the following enzymes is correctly matched with their substrate? chymotrypsin/amino acids sucrase/disaccharides lipase/peptides pepsin/pepsinogen

pepsin/pepsinogen

Gastrointestinal movement whereby food is propelled along the gut is referred to as:

peristalsis

Which of the following passageways is shared by both the respiratory and digestive systems?

pharynx

Which of the following lists the correct order of structures in the digestive system?

pharynx, esophagus, stomach, small intestine, large intestine

The enzyme pepsin digests

proteins

The region of the stomach that empties into the duodenum is the

pylorus

Which of the following is a remnant of the fetal umbilical vein?

round ligament

The pancreas:

secretions contain bicarbonate to neutralize acid

The event which increases the secretion of serous (watery) saliva is:

signals from the parasympathetic nervous system

Most nutrients in the foods we eat are absorbed where?

small intestine

The absorption of fatty acids occurs via:

specialized lymph structures called lacteals in the duodenum

Cholecystokinin (CCK) is necessary in the digestive process because it:

stimulates the release of bile from the gallbladder and enzymes from the pancreas

Chemical breakdown of materials by acid and enzymes takes place in the

stomach

The gallbladder:

stores bile

The oral mucosa has ________ epithelium.

stratified squamous

Which of the following is not a salivary gland? -parotid gland -submandibular gland -submaxillary gland -sublingual gland

submaxillary gland

Large blood vessels and lymphatics are found in the

submucosa

The bacteria in the large intestine function primarily to:

synthesize vitamins B and K

The pressure within the stomach would tend to force the contents of the stomach into the esophagus. However, this does not occur because of:

the gastroesophageal sphincter (cardiac sphincter)

Stimulation of secretions from the pancreas may be caused by:

the presence of acid in the small intestine

Which of the following will stimulate the secretion of hydrochloric acid by the stomach? -the secretion gastrin -the presence of fat in the small intestine -hypertonic solution in the duodenum -all of the above

the secretion gastrin

True or False: Stimulation of the vagus nerve increases activity in the gastrointestinal tract.

true

Which of the following enzymes is specific for proteins? -dextrinase -lactase -trypsin -lipase

trypsin

A structure that helps prevent food from entering the pharynx prematurely is the

uvula

Enzymes involved in the digestion of carbohydrates are secreted by:

-Cells of the colon -Pancreas

The large intestine:

-contains a normal flora of bacteria -has epiploic appendages on its surface -has haustra and teniae coli

The Kupffer cells of the liver

-destroy damaged RBCs. -destroy bacteria. -present antigens. -are phagocytic

The activities of the digestive system are regulated by

-hormones. -parasympathetic and sympathetic neurons. -the contents of the digestive tract. -intrinsic nerve plexuses.

Movement of the gastrointestinal tract is characterized by:

-local, segmental contractions to churn food -waves of contraction to move food uni-directionally through the tract

Functions of the tongue

-manipulation to assist with chewing -mechanical processing -sensory analysis -secretion of mucins

The secretion of acid and enzymes by the gastric mucosa is controlled and regulated by

-the central nervous system. -short reflexes coordinated in the stomach wall. -digestive tract hormones

During swallowing:

-the soft palate and uvula move up -the vocal folds should be in a parallel position -peristalsis occurs in the esophagus

The secondary dentition usually has how many teeth?

32