The chemical breakdown of food into small organic fragments that can be absorbed by the digestive epithelium is __________.
Digestion
Which layer of the digestive tract is responsible for peristalsis and segmentation?
The muscularis externa contains muscle layers responsible for the processes of peristalsis and segmentation.
In the oral cavity, the digestive enzyme _________ is found in saliva and begins the digestion of _________.
amylase;starch
Which oral structure(s) is (are) responsible for manipulating food to assist in chewing and in the production of the enzyme lipase?
Tongue
Which type of tooth is responsible for clipping and cutting?
Incisor
Which regions of the pharynx serve as passageways for food on its way to the esophagus?
oropharynx and laryngopharynx
The lowest portion of the stomach, which forms the sharp curve of the J shape of the stomach, is the __________.
pylorus
Which of the following phases of gastric activity is caused by the sight, taste, or thought of food?
cephalic phase
What is the term for swallowing?
deglutition
A series of transverse folds in the small intestine that serve to increase the surface area for absorption are the __________.
plicae circulares
Which of the following is NOT produced by the gastric glands in the stomach of an adult?
intrinsic factor
rennin
pepsinogen
HCl
Rennin
Which of the following is NOT a region of the small intestine?
jejunum
ileum
cecum
duodenum
Cecum
What is the function of bile?
To emulsify lipids.
The pancreas produces digestive enzymes that digest __________.
carbohydrates, lipids, proteins, and nucleic acids
A small, slender structure that is attached to the large intestine and is dominated by lymphoid nodules is the __________.
appendix
The reflex that occurs in the large intestine and promotes the movement of feces toward the anus is the __________.
defecation reflex
Which of the following is NOT an effect of advancing age on the digestive system?
stronger peristaltic contractions, resulting in diarrhea
increase in peptic ulcers
increase in dental caries and gingivitis, resulting in loss of teeth
increase in the rate of digestive system cancer
Answer: stronger peristaltic contractions, resulting in diarrhea because
**Peristaltic contractions become weaker, resulting in constipation.**
Which of the following are NOT absorbed in the large intestine?
organic wastes, such as urobilinogens
water
certain vitamins, such as vitamin K
All of the listed substances are absorbed by the large intestine.
All of the listed substances are absorbed by the large intestine.
Which of the following does NOT digest a carbohydrate?
sucrase
pancreatic alpha-amylase
lactase
pancreatic lipase
pancreatic lipase
Which of the following does NOT digest a protein?
nuclease
trypsin
pepsin
enteropeptidase
nuclease
Put the following structures involved in bile transport in the proper order, from the liver to the gallbladder and on to the small intestine, by matching them (1) through (6):
Common bile duct
Bile ductules
Right and left hepatic ducts
Bile canaliculi
Common hepatic duct
Cystic duct
Bile canaliculi
Bile ductules
Right and left hepatic ducts
Common hepatic duct
Cystic duct
Common bile duct
Match the following cells and glands with their correct products:
Parietal Cell, Chief Cell, G cells, Intestinal glands, Brunner glands
Parietal Cell- HCl
Chief Cell- Pepsinogen
G cells- Gastrin
Intestinal glands-CCK (Cholecystokinin)
Brunner glands-Urogastrone
Match the following substrates and products with the enzyme that catalyzes the reaction:
1. Proteins to short-chain polypeptides
2. Dipeptides and tripeptides to amino acids
3. Trypsinogen to trypsin
4. A disaccharide to monosaccharides
1. Pepsin
2. Exopeptidase
3. Enteropeptidase
4. Lactase
This stimulates of increased motility in the stomach and the production of acids and enzymes.
Gastrin
Secreted when fats and especially glucose enters the intestine, this enzyme triggers the release of insulin at the pancreas.
Gastric inhibitory peptide
This is secreted when chyme is rich in lipids and partially digested proteins. It triggers the opening of the hepatopancreatic sphincter.
CCK (Cholecystokinin)
This is released when chyme enters the small intestine and it stimulates mucin production.
Enterocrinin
Match the organ of the digestive system with its function:
1. Mastication of food
2. Carries solid foods and liquids to the stomach
3. Bulk storage of ingested food, chemical and mechanical breakdown of ingested food, and production of the intrinsic factor
4. Digestion and absorption of nutrients
5. Reabsorption of water, absorption of important vitamins, and storage of fecal matter
6. Temporary storage of fecal matter
1. Teeth
2. Esophagus
3. Stomach
4. Small Intestine
5. Large intestine
6. Rectum
Which of the following is a function of the digestive tract?
excretion
absorption
ingestion
digestion
All of the listed responses are correct.
All of the listed responses are correct.
From the outside in, the correct order of the layers of the digestive tract is _________.
serosa, muscularis externa, submucosa, mucosa
The movements of the muscularis externa are coordinated by the _________.
myenteric plexus
Waves of smooth muscle contraction that propel materials along the digestive tract are called _________.
peristalsis
The mesentery that hangs like an apron from the lateral and inferior portion of the stomach is the _________.
greater omentum
Which layer of the digestive tract contains large blood vessels, lymphatics, and a network of nerve fibers called the plexus of Meissner?
submucosa
The lingual frenulum _________.
connects the tongue to the floor of the oral cavity
may need to be cut if the condition of ankyloglossia exists
is a thin fold of mucous membrane
All of the listed responses are correct.
All of the listed responses are correct.
Incisors are used for _________.
clipping or cutting
Which of the following statements is FALSE concerning the teeth?
1. A layer of a material called cementum covers the dentin of the root and attaches the tooth to the periodontal ligament.
2. Brushing your teeth and massaging your gums stimulate the growth of epithelial cells that attach to the tooth, thus promoting tooth attachment.
3. Dentin, the material that makes up the enamel of the teeth, is a type of spongy bone, thus giving the tooth its hardness.
4. The bicuspids have flattened crowns with prominent ridges used for crushing food.
Dentin, the material that makes up the enamel of the teeth, is a type of spongy bone, thus giving the tooth its hardness.
Which salivary glands produce a thick serous secretion containing large amounts of salivary amylase?
parotid glands
Which type of tooth is conical with a pointed tip and is used for tearing and slashing?
cuspids or canines
The mucosa and submucosa of the esophagus are folded _________.
to allow the expansion of the esophagus during the passage of a large bolus
What occurs during the pharyngeal phase of deglutition?
The larynx elevates, and the uvula and soft palate block the nasopharynx.
Which of the following is a function of the stomach?
mechanical breakdown of food
production of intrinsic factor
emulsification of fats
both mechanical breakdown of food and production of intrinsic factor
both mechanical breakdown of food and production of intrinsic factor
Chief cells secrete _________.
pepsinogen
When the stomach is empty, the mucosa is thrown into folds called _________.
rugae
When you walk into a Mexican restaurant and smell the savory aroma of fajitas, which phase of gastric activity is triggered?
cephalic phase
Peyer patches are _________.
lymphoid nodules located in the ileum
The wall of the small intestine bears a series of folds called the __________.
plicae circulares
The duodenum differs from the rest of the small intestine in that its submucosa contains many __________ that secrete mucus.
Brunner glands
The gastroenteric reflex stimulates motility __________.
along the entire length of the small intestine
Sympathetic stimulation __________.
stimulates submucosal glands
inhibits submucosal glands
stimulates peristalsis
None of the listed responses is correct.
inhibits submucosal glands
Concentrated crystals of minerals and salts in the gallbladder produce __________.
a condition called cholelithiasis
Pancreatic juice is __________.
alkaline
Which of the following is NOT a function of the liver?
metabolic regulation
bile production
hematologic regulation
immunologic regulation
immunologic regulation
Liver cells, or hepatocytes, receive blood from the __________.
both the hepatic artery and hepatic portal vein
Bile acts as __________.
an enzyme
a remover of toxins
an emulsifier
All of the listed responses are correct.
an emulsifier
Which of the following products of digestion is NOT taken up by capillaries in the small intestine?
chylomicrons
minerals
amino acids
simple sugars
chylomicrons
Which of the following is NOT a pancreatic enzyme?
lipase
alpha-amylase
trypsinogen
pepsinogen
nuclease
pepsinogen
Which of the following statements is FALSE regarding the Kupffer cells of the liver?
Kupffer cells are fixed macrophages of the immune system.
Kupffer cells have the ability to produce bile.
Kupffer cells have the ability to store heavy metals, such as tin and
mercury.
Kupffer cells phagocytize and process foreign materials passing by
them in the bloodstream.
Kupffer cells have the ability to produce bile.
Peyer patches are associated with which region of the intestine?
ileum
Treatment for a morbidly obese man includes surgery to reduce the length of his intestine. Which region of the small intestine should be removed to achieve greatest weight loss?
jejunum
The defecation reflex __________.
involves long and short reflexes and involves two positive feedback loops
The large intestine absorbs which of the following vitamins from colonic bacteria?
vitamin K
biotin
vitamin B5, or pantothenic acid
All of the listed responses are correct.
All of the listed responses are correct.
Of the 1500 mL of material that enters the large intestine on a daily basis, approximately how much water in the material is reabsorbed?
1300 mL
Which of the following occurs during the defecation reflex?
Parasympathetic centers in the sacral region of the spinal cord stimulate mass movements.
Fat-soluble vitamins move across the intestinal mucosa by __________.
diffusion
Which of the following is NOT a brush border enzyme?
amylase
maltase
lactase
dipeptidase
amylase
Fatty acids and monoglycerides interact with the bile salts in chyme to form small, lipid–bile salt complexes called __________.
micelles
Which of the following statements is FALSE concerning aging and the digestive system?
Motility decreases, and peristaltic contractions become weaker.
The rate of division of epithelial stem cells decreases.
Dehydration becomes less common as a result of the body's inability to
effectively rid itself of water.
Rates of cancer in the colon and stomach increase because immune
system activity decreases.
Dehydration becomes less common as a result of the body's inability to effectively rid itself of water.
True/False. The pharynx belongs to both the respiratory and digestive systems.
True. As air is inhaled it passes through the pharynx into the trachea, and as food is swallowed it passes through the pharynx into the esophagus.
True/False. Cuspids are cutting or clipping teeth.
False. Cuspids are tearing or slashing teeth.
True/False. A drop in the pH of the chyme coming from the stomach triggers the release of CCK.
False. CCK is a hormone released when chyme is full of fatty acids and triglycerides.
True/False. The haustra are formed by contraction of the taenia coli.
True. Expansion and elongation of the colon is accomplished by haustra; how do the haustra expand and elongate?
True/False. The region of the tooth between the crown and the root is called the gingival space.
False. The neck of the tooth is found between the crown and the root.
The muscularis externa propels materials from one portion of the digestive tract to the other by a series of wavelike contractions called peristalsis, while in most areas of the small intestine _____ movements churn and fragment digestive materials.
segmentation
Pancreatic juice is secreted by units known as pancreatic __________.
acini
__________ are proteolytic enzymes that break small peptide chains into amino acids.
Peptidases
The transverse folds that make up the intestinal lining and provide more surface area for absorption are called __________.
plicae circulares
The glycoprotein __________, necessary for vitamin B12 absorption, is produced in the stomach.
intrinsic factor
Which of the following digestive regions is responsible for the propulsion of materials into the esophagus?
pharynx
The active process that occurs when materials enter the digestive tract via the mouth is _________.
ingestion
Sympathetic stimulation of the muscularis externa promotes _________.
muscular inhibition and relaxation
Which of the following statements about peritonitis is FALSE?
It leads to inflammation of the digestive mucosa.
It is an inflammation of the peritoneal membrane.
It can be caused by bacteria entering the abdominal cavity during a
surgical procedure.
It could be caused by a burst appendix.
It leads to inflammation of the digestive mucosa.
Which of the following major layers of the digestive tract is described as a layer of dense irregular connective tissue filled with blood vessels and the plexus of Meissner?
submucosa
Strong contractions from the transverse colon to the rest of the large intestine that move the contents of the colon toward the sigmoid colon are called _________.
mass movements
Which of the following salivary glands produce salivary amylase, a carbohydrate-digesting enzyme?
both parotid glands and submandibular salivary glands
Which of the following is NOT a function of saliva?
lubrication of the mouth
initial digestion of proteins
initial digestion of carbohydrates
lubrication of food
initial digestion of proteins
The three pairs of salivary glands that secrete into the oral cavity include the _________.
parotid, sublingual, and submandibular
Crushing, mashing, and grinding of food are best accomplished by the action of the _________.
bicuspids
The three phases of deglutition are _________.
buccal, pharyngeal, and esophageal
On its way to the esophagus, food normally passes through the _________.
oropharynx and laryngopharynx
lower esophageal sphincter
pharyngeal sphincter
All of the listed responses are correct.
oropharynx and laryngopharynx
The pharyngeal muscles that push the food bolus toward the esophagus are the _________.
pharyngeal constrictor muscles
Solid food and liquids are carried from the pharyngeal region to the stomach by the _________.
esophagus
The inferior end of the esophagus normally remains in a state of active contraction that _________.
prevents the backflow of materials from the stomach into the esophagus
Gastric secretion is inhibited by _________.
secretin
Which of the following is secreted by the stomach?
gastrin
Which division of the small intestine contains the Brunner glands?
duodenum
Which of the following enzymes is NOT found in pancreatic juice?
pepsin
lipase
amylase
chymotrypsin
pepsin
Bile entering the gallbladder must pass through the _________.
cystic duct
Which hormone promotes the flow of bile and of pancreatic juice containing enzymes?
cholecystokinin
The longitudinal ribbons of smooth muscle visible on the outer surfaces of the colon just beneath the serosa are the _________.
taenia coli
The vermiform appendix is dominated by what type of lymphatic structures in the mucosa and submucosa?
lymphoid nodules
Which vitamins are liberated by bacterial action and absorbed in the large intestine?
biotin, pantothenic acid, and vitamin K
Which of the following organic nutrients are NOT absorbed by capillaries in the intestinal villi?
carbohydrates
lipids
proteins
None of the listed responses is correct.
lipids
The nutrients that can be absorbed without preliminary processing but may involve special transport mechanisms are _________.
water, electrolytes, and vitamins
The enzyme lactase, which digests lactose to glucose and galactose, is synthesized by _________.
the brush border of the small intestine
Which of the following is NOT a function of hydrochloric acid in the stomach?
facilitating protein digestion
killing microorganisms
breaking down disaccharides into monosaccharides
activating pepsin
breaking down disaccharides into monosaccharides
The intestinal epithelium absorbs monosaccharides by _________.
facilitated diffusion and cotransport mechanisms
When two fluids are separated by a selectively permeable membrane, water tends to flow into the solution that has the _________.
higher concentration of solutes (lesser concentration of water)
An error in swallowing could most likely be detected by the _________.
larynx
Many visceral smooth muscle networks show rhythmic cycles of activity in the absence of neural stimulation because of _________.
pacesetter cells that spontaneously depolarize and trigger contraction of entire muscular sheets
Why can a completely dry food bolus NOT be swallowed?
Friction with the walls of the esophagus makes peristalsis ineffective.
Gastric glands, which produce most of the gastric juice, are abundant in which of the following regions of the stomach?
both fundus and body
Which two factors play an important part in the movement of chyme from the stomach to the small intestine?
stomach distension and gastrin release
The plicae of the intestinal mucosa, which bears the intestinal villi, are structural features that _________.
increase the total surface area for absorption
The enteroendocrine cells of the intestinal crypts are responsible for producing which intestinal hormones?
cholecystokinin and secretin
Villikinin, motilin, and somatostatin are produced in the _________.
small intestine
The primary functions of intestinal juice include which of the following?
to moisten the chyme
to assist in buffering acids
to dissolve digestive enzymes and the products of digestion
All of the listed responses are correct.
All of the listed responses are correct.
Which of the following causes an immediate increase in the rates of glandular secretion and peristaltic activity in all segments of the small intestine?:
gastroenteric reflex
The primary effect of secretin is to cause _________.
an increase in secretion of bile and buffers by the liver and the pancreas
Which peptide hormone causes the release of insulin from the pancreatic islets?
GIP
How does the mucosa of the rectum compare with that of the colon and cecum?
The colon and cecum are lined with a simple columnar epithelium for absorption, whereas the rectum is lined with stratified squamous epithelium because it is next to an opening to the exterior.
The muscular sphincter that guards the entrance between the ileum and the cecum is the _________.
ileocecal valve
Which produces the LEAST number of contractions to force food through the digestive tract on a daily basis?
large intestine
What is the average composition of the fecal waste material?
75 percent water; 5 percent bacteria; 20 percent indigestible materials, inorganic matter, and epithelial remains
The hormone gastrin _________.
increases the activity of parietal and chief cells
The two positive feedback loops involved in the defecation reflex are _________.
stretch receptors in rectal walls, and the sacral parasympathetic system
The "doorway to the liver" (porta hepatis) is a complex that includes the _________.
bile duct, hepatic portal vein, and hepatic artery
Triglycerides coated with proteins create a complex known as a _________.
chylomicron