Chapter 17 Digestive System
1. List and describe the locations of the major parts of the alimentary canal.
a. Mouth—the oral cavity.
b. Pharynx—extends from the back of the nasal cavity to the top of the esophagus.
c. Esophagus—extends from the pharynx to the stomach.
d. Stomach—just below the diaphragm on the left side of the body.
e. Small intestine—extends from the stomach to the large intestine.
f. Large intestine—extends from the small intestine to the anus.
2. List and describe the location of the accessory organs of the digestive system.
a. Salivary glands—located in the oral cavity.
b. Liver—lies just below the diaphragm on the right side of the body.
c. Gallbladder—lies on posterior side of the liver.
d. Pancreas—located behind the stomach, attached to the duodenum.
3. Name the four layers of the wall of the alimentary canal.
a. Mucosa or mucous membrane
b. Submucosa
c. Muscular layer
d. Serosa or serous layer
4. Distinguish between mixing movements and propelling movements.
A mixing movement is a wavelike motion back and forth. A propelling movement is one where the
muscle contraction occurs in the wall of the tube but the muscles just ahead in the tube relax.
5. Define peristalsis.
Peristalsis is defined as the rhythmic propelling movements that occur in the alimentary canal.
6. Explain the relationship between peristalsis and receptive relaxation.
Receptive relaxation is where the muscular wall ahead of peristaltic contraction relaxes. This
allows the tubular contents to be pushed along the canal.
7. Describe the general effects of parasympathetic and sympathetic impulses on the alimentary
canal.
Parasympathetic impulses generally increase the activity of the digestive system. Sympathetic
impulses generally are opposite of the parasympathetic impulses, thereby decreasing the activity of
the digestive system. This would then mean that peristalsis increases when innervated by the
parasympathetic nervous system and would decrease when innervated by the sympathetic nervous
system.
8. Discuss the functions of the mouth and its parts.
The mouth receives food and prepares it for digestion by mechanically breaking up the size of solid
particles and mixing them with saliva. The cheeks are the outer layers of skin, pads of subcutaneous
fat, and the muscles associated with expression and chewing. The lips are highly mobile structures
that contain skeletal muscles and the sensory receptors that surround the mouth. They are used in
distinguishing the temperature and texture of foods. The tongue is a body of skeletal muscle and taste
receptors. The function of the tongue is to mix food particles with saliva during chewing and move
food toward the pharynx during swallowing.
9. Distinguish among the lingual, palatine, and pharyngeal tonsils.
The lingual tonsils are found on the root of the tongue and are rounded masses of lymphatic tissues.
The palatine tonsils are masses of lymphatic tissues found in the back of the mouth, on either side of
the tongue, and closely associated with the palate. The pharyngeal tonsils, also known as the
adenoids, are masses of lymphatic tissue that occur on the posterior wall of the pharynx, above the
border of the soft palate.
10. Compare the primary and secondary teeth.
Primary teeth are the first set of teeth that erupt through the gums at regular intervals between the
ages of six months and two and one-half years. There are twenty primary teeth - ten in each jaw. The
secondary teeth begin to appear about age six but may not be completed until somewhere between
ages seventeen and twenty-five. There are thirty-two secondary teeth - sixteen in each jaw.
11. Explain how the various types of teeth are adapted to perform specialized functions.
The incisors are chisel-shaped, and their sharp edges bite off relatively large pieces of food. The
cuspids are cone-shaped, and they grasp and tear food. The bicuspids and molars have somewhat
flattened surfaces and are specialized for grinding food particles.
12. Describe the structure of a tooth.
Each tooth consists of two main portions called the crown and the root. The crown is the portion
above the gum and is covered by glossy white enamel. Beneath the enamel is the bulk of the tooth,
which is made up of dentin. Dentin surrounds the central cavity, which houses the blood vessels,
nerves and connective tissue. The root is enclosed by cementum, which is surrounded by the
periodontal ligament. The region where the crown and root meet is called the neck.
13. Explain how a tooth is anchored in its socket.
Cementum and the periodontal ligament anchor the tooth.
14. List and describe the locations of the major salivary glands.
The parotid glands are the largest salivary glands and are located in front of, and somewhat below,
each ear between the skin of the cheek and the masseter muscle. The submandibular glands are
located in the floor of the mouth on the inside surface of the lower jaw. The sublingual glands are the
smallest of the salivary glands and are on the floor of the mouth under the tongue.
15. Explain how the secretions of the salivary glands differ.
The parotid glands secrete a clear, watery fluid that is rich in amylase. The submandibular glands
secrete a serous fluid with some mucous, making it more viscous than the parotid gland secretion. The
sublingual glands secrete a thick and stringy mucous fluid.
16. Discuss the digestive functions of saliva.
The serous cells found in the salivary glands produce a watery fluid that contain amylase. Amylase is
a digestive enzyme that splits starch and glycogen molecules into disaccharides. This is the first step
of carbohydrate digestion.
17. Name and locate the three major regions of the pharynx.
a. Nasopharynx—located above the soft palate.
b. Oropharynx—located behind the soft palate and projects downward to the upper border of the
epiglottis.
c. Laryngopharynx—located from the upper border of the epiglottis downward to the lower border
of the cricoid cartilage of the larynx.
18. Describe the mechanism of swallowing.
The steps in the mechanism of swallowing are:
a. The soft palate raises, preventing food from entering the nasal cavity.
b. The hyoid bone and the larynx are elevated; the epiglottis closes off the top of the trachea so that
food is less likely to enter.
c. The tongue is pressed against the soft palate, sealing off the oral cavity from the pharynx.
d. The longitudinal muscles in the pharyngeal wall contract, pulling the pharynx upward toward the
food.
e. The lower portion of the inferior constrictor muscles relaxes, opening the esophagus.
f. The superior constrictor muscles contract, stimulating a peristaltic wave to begin in the
pharyngeal muscles. This wave forces the food into the esophagus.
19. Explain the functions of the esophagus.
The esophagus functions as a tube that transports substances from the pharynx to the stomach.
20. Describe the structure of the stomach.
The stomach is a J-shaped, pouchlike organ. Thick folds called rugae mark its inner lining. Its
mucous membrane lining contains the gastric pits that are the openings for the gastric glands that
secrete digestive enzymes.
21. List the enzymes in gastric juice, and explain the function of each enzyme.
a. Pepsin—is a protein-splitting enzyme, which is the beginning of nearly all types of dietary
protein. The chief cells secrete pepsinogen (the precursor of pepsin) that then combines with
hydrochloric acid to form pepsin.
b. Intrinsic factor—aids in the absorption of vitamin B12.
22. Explain how gastric secretions are regulated.
Parasympathetic impulses and the hormone gastrin enhance the gastric secretions. The presence of
the food in the small intestine reflexly inhibits the gastric secretions.
23. Describe the mechanism that controls the emptying of the stomach.
The chyme accumulates near the pyloric sphincter. This muscle begins to relax. The pyloric region of
the stomach then pumps the chyme a little at a time into the small intestine. The rate at which the
stomach empties is dependent upon the fluidity of the chyme and the type of food present.
24. Describe the enterogastric reflex.
The enterogastric reflex inhibits the gastric peristalsis and the secretion when the food enters the
small intestine.
25. Explain the mechanism of vomiting.
Sensory impulses travel from the site of stimulation to the vomiting center in the medulla oblongata,
and a number of motor responses follow. These include taking a deep breath, raising the soft palate
and thus closing the nasal cavity, closing the opening to the trachea (glottis), relaxing the circular
muscle fibers at the base of the esophagus, contracting the diaphragm so that it moves downward over
the stomach, and contracting the abdominal wall muscles so that pressure inside the abdominal cavity
increases. As a result, the stomach is squeezed from all sides, forcing its contents upward and out
through the esophagus, pharynx, and mouth.
26. Describe the locations of the pancreas and the pancreatic duct.
The pancreas is an elongated, somewhat flattened organ that is posterior to the stomach and behind
the parietal peritoneum. It is attached to the duodenum by the pancreatic duct, which runs the length
of the pancreas.
27. List the enzymes in pancreatic juice, and explain the function of each enzyme.
a. Pancreatic amylase—functions to digest carbohydrates.
b. Pancreatic lipase—functions to digest triglycerides.
c. Trypsin—functions to digest protein.
d. Chymotrypsin—functions to digest protein.
e. Carboxypeptidase—functions to digest protein.
f. Nucleases—functions to break nucleic acids into nucleotides.
28. Explain how pancreatic secretions are regulated.
Secretin stimulates the release of pancreatic juice that has a high bicarbonate ion concentration.
Cholecystokinin stimulates the release of pancreatic juice that has a high concentration of digestive
enzymes. Acidic chyme in the duodenum triggers the release of pancreatic juice. As the chyme moves
through the intestine the pancreatic juice is inhibited.
29. Describe the structure of the liver.
The liver is enclosed in a fibrous capsule and divided into lobes by connective tissue. Each lobe is
further subdivided into hepatic lobules. These are the functional units of the liver. Each lobule
consists of hepatic cells that radiate outward from a central vein.
30. List the major functions of the liver.
a. Carbohydrate metabolism
b. Lipid metabolism
c. Protein metabolism
d. Glycogen and vitamin storage
e. Blood filtering
f. Detoxification
g. Secretion of bile
31. Describe the composition of bile.
Bile is composed of bile salts, bile pigments (bilirubin and biliverdin), cholesterol, and electrolytes.
32. Trace the path of bile from a bile canal to the small intestine.
The bile flows from the bile canal into hepatic ducts. The ducts then merge to form the common
hepatic duct. It then can flow into the gallbladder for storage. The common hepatic and cystic duct
form the common bile duct. This then empties into the duodenum.
33. Explain how gallstones form.
Gallstones form as a result of cholesterol precipitating out of solution and crystallizing. This can
result if the bile becomes too concentrated, the hepatic cells secrete too much cholesterol, or the
gallbladder is inflamed.
34. Define cholecystokinin.
Cholecystokinin is a hormone that is released in response to chyme in the duodenum. It then triggers
the release of pancreatic juice from the pancreas, and bile from storage in the gallbladder.
35. Explain the functions of bile salts.
Bile salts emulsify fats and aid in the absorption of fatty acids, cholesterol, and certain vitamins.
36. List and describe the locations of the parts of the small intestine.
a. Duodenum—the first twenty-five centimeters of the small intestine, it lies behind the parietal
peritoneum. It is the most fixed portion of the small intestine.
b. Jejunum—the proximal two-fifths of the remainder of the small intestine.
c. Ileum—the remainder of the small intestine.
37. Name the enzymes of the intestinal mucosa, and explain the function of each enzyme.
a. Peptidases—splits peptides into amino acids.
b. Sucrase—splits sucrose into glucose.
c. Maltase—splits maltose into fructose.
d. Lactase—splits lactose into galactose.
e. Intestinal lipase—splits fats into fatty acids and glycerol.
38. Explain regulation of the secretions of the small intestine.
These secretions are stimulated by the direct contact with chyme, which provides both chemical and
mechanical stimuli, and by reflexes triggered by distention of the intestinal wall. It is inhibited by the
lack of chyme in the small intestine.
39. Describe the functions of the intestinal villi.
a. The villi serve to increase the surface area of the intestinal wall.
b. Monosaccharides, amino acids, fatty acids, and glycerol are absorbed by the villi.
c. Fat molecules with longer chains of carbon atoms enter the lacteals of the villi.
d. Other digestive products enter the villi and are carried away by the blood.
40. Summarize how each major type of digestive product is absorbed.
a. Monosaccharides are absorbed by the villi by diffusion, facilitated diffusion, or active transport.
The blood then carries them away.
b. Amino acids are absorbed by the villi by means of active transport. The blood then carries them
away.
c. Fatty acids and glycerol are absorbed by diffusion into the lacteals of the villi. They are then
carried away by lymph.
d. Diffusion and active transport into the villi absorb electrolytes.
e. Water is absorbed by osmosis into the villi.
41. Explain control the movement of the intestinal contents.
The major mixing movement is segmentation, in which small, ringlike, contractions occur
periodically, cutting the chyme into segments moving it back and forth. Peristaltic waves propel the
chyme through the small intestine. These are weak waves so that the chyme moves slowly through the
small intestine.
42. List and describe the locations of the parts of the large intestine.
The cecum is a dilated, pouchlike structure that hangs slightly below the ileocecal opening. This
represents the beginning of the large intestine. The colon is divided into four parts. The ascending
colon begins at the cecum and travels upward against the posterior abdominal wall to a point just
below the liver. It turns sharply to the left and becomes the transverse colon. This is the longest and
most movable part of the large intestine. As the transverse colon approaches the spleen, it turns
abruptly downward and becomes the descending colon. At the brim of the pelvis, the descending
colon makes an S-shaped curve, called the sigmoid colon, and then becomes the rectum. The rectum
is firmly attached to the sacrum and it ends about five centimeters below the tip of the coccyx. It now
is known as the anal canal. The anal canal is the last two and one-half to four centimeters of the large
intestine. It ends at the anus, which opens to the outside of the body.
43. Explain the general functions of the large intestine.
a. It has little or no digestive function.
b. It secretes mucous.
c. Absorption is generally limited to water and electrolytes.
d. Formation and storage of feces.
44. Describe the defecation reflex.
A person holds a deep breath and contracts the abdominal wall muscles. This increases the internal
abdominal pressure and forces the feces into the rectum. As the rectal wall distends, this triggers the
defecation reflex. Peristaltic waves in the descending colon are stimulated, and the internal anal
sphincter relaxes. The external sphincter relaxes and the feces are forced to the outside.
45. What are the effects of altered rates of absorption, due to aging, in the small intestine?
Because the small intestine is the site of absorption of nutrients, it is here that noticeable signs of
aging on digestion arise. Subtle shifts in the microbial species that inhabit the small intestine alter the
rates of absorption of particular nutrients. With age, the small intestine becomes less efficient at
absorbing vitamins A, D, and K and the mineral zinc. This raises the risk of deficiency symptoms—
effects on skin and vision due to a lack of vitamin A; weakened bones from inadequate vitamin D;
impaired blood clotting seen in vitamin K deficiency; and slowed healing, decreased immunity, and
altered taste evidenced in zinc deficiency.
46. How does digestive function change with age?
Older people sometimes do not chew food thoroughly because thinning enamel makes teeth more
sensitve to hot and cold foods, gums recede, and teeth may loosen.
Slowing peristalsis in the digestive tract may cause heartburn and constipation.
Aging affects nutrient absorption in the small intestine.
Accessory organs to digestion also age, but not necessarily in ways that affect health.
Chapter 17: Digestive System
I. Introduction
A. Digestion is _________________________________________________________________
B. Mechanical digestion breaks ____________________________________________________
______________________________________________________________________________
C. Chemical digestion breaks ______________________________________________________
D. The organs of the digestive system carry out the processes of __________________________
______________________________________________________________________________
E. The alimentary canal is composed of ______________________________________________
______________________________________________________________________________
F. The accessory organs of the digestive system are ____________________________________
______________________________________________________________________________
II. General Characteristics of the Alimentary Canal
A. Introduction
1. The alimentary canal is a _______________________________________________ tube that passes through
________________________________________________________________________________________
2. The structure of __________________, how it ___________________________________________ , and its
innervation are similar ______________________________________________________________________
B. Structure of the Wall
1. The four layers of the alimentary wall are____________________________________
_______________________________________________________________________
2. The mucosa is located ______________________________________________ and is
composed of _____________________________________________________________
3. The functions of the mucosa are ___________________________________________
_______________________________________________________________________
4. The submucosa is located ___________________________________________ and is
composed of _____________________________________________________________
5. The functions of the submucosa are ________________________________________
_______________________________________________________________________
6. The muscular layer is located ________________________________________ and is
composed of _____________________________________________________________
7. When the circular fibers contract, the diameter of the tube_______________________
8. When the longitudinal fibers contract, the tube________________________________
9. The serosa layer is located___________________________________________ and is
composed of _____________________________________________________________
10. The functions of the serosa are ___________________________________________
_______________________________________________________________________
C. Movements of the Tube
1. The two types of motor functions of the alimentary canal are ____________________
_______________________________________________________________________
2. Mixing occurs when ____________________________________________________
_______________________________________________________________________
3. Peristalsis is ___________________________________________________________
4. Peristalsis occurs when __________________________________________________
_______________________________________________________________________
D. Innervation of the Tube
1. Branches of ___________________________________________________ innervate
the alimentary canal.
2. The innervation of the alimentary canal maintains _____________________________
and regulates _____________________________________________________________
3. The submucosal plexus is important for _____________________________________
4. The myenteric plexus is important for_______________________________________
5. The functions of parasympathetic impulses are _______________________________
_______________________________________________________________________
6. The functions of sympathetic impulses are ___________________________________
_______________________________________________________________________
III. Mouth
A. Introduction
1. The functions of the mouth are ____________________________________________
2. Mastication is _________________________________________________________
3. The mouth is surrounded by ______________________________________________
_______________________________________________________________________
4. The oral cavity is _______________________________________________________
5. The vestibule of the mouth is _____________________________________________
B. Cheeks and Lips
1. The cheeks form _____________________________________________________________________ and
consist of ________________________________________________________________________________
2. The lips surround _____________________________________________________________________ and
consist of ________________________________________________________________________________
3. The reddish color of lips is due to ___________________________________________________________
C. Tongue
1. The tongue is located____________________________________________________
2. _____________________________________________ membranes cover the tongue.
3. The frenulum of the tongue is _____________________________________________
4. The body of the tongue is composed of______________________________________
_______________________________________________________________________
5. Muscles of the tongue function to __________________________________________
6. Papillae of the tongue are ________________________________________________
7. Functions of papillae are _________________________________________________
8. The root of the tongue is anchored to _______________________________________
9. Lingual tonsils are located ________________________________________________
D. Palate
1. The palate forms ____________________________________________________ and
consists of _______________________________________________________________
2. The hard palate is formed by ______________________________________________
3. The soft palate is formed by ______________________________________________
4. The uvula is ___________________________________________________________
5. The function of the uvula is_______________________________________________
_______________________________________________________________________
6. Palatine tonsils are located _______________________________________________
7. Pharyngeal tonsils are located _____________________________________________
E. Teeth
1. The primary teeth are ___________________________________________________
2. The secondary teeth are __________________________________________________
3. The secondary teeth consist of ____________________________________________
4. The arrangement of secondary teeth are _____________________________________
_______________________________________________________________________
5. Wisdom teeth are _______________________________________________________
6. Chewing increases ______________________________________________________
7. Incisors are specialized to ________________________________________________
8. Cuspids are specialized to ________________________________________________
9. Bicuspids and molars are specialized to _____________________________________
10. The crown of a tooth is _________________________________________________
11. The root of a tooth is ___________________________________________________
12. The neck of a tooth is __________________________________________________
13. Enamel consists of _____________________________________________________
14. Dentin is ____________________________________________________________
15. The root canal is located _____________________________________________ and
contains_________________________________________________________________
16. The pulp cavity is located ____________________________________________ and
contains_________________________________________________________________
17. Cementum is _________________________________________________________
18. A periodontal ligament is _______________________________________________
IV. Salivary Glands
A. Introduction
1. Salivary glands secrete __________________________________________________
2. The functions of saliva are _______________________________________________
_______________________________________________________________________
3. The three pairs of major salivary glands are __________________________________
_______________________________________________________________________
B. Salivary Secretions
1. Two cell types of salivary glands are _______________________________________
2. Serous cells produce ____________________________________________________
3. Mucous cells produce ___________________________________________________
4. Amylase digests________________________________________________________
5. Salivary glands are innervated by both ______________________________________
_______________________________________________________________________
6. Sympathetic fibers stimulate the glands to ___________________________________
7. Parasympathetic fibers stimulate the glands to ________________________________
_______________________________________________________________________
C. Major Salivary Glands
1. The largest of the major salivary glands is ___________________________________
2. The parotid glands are located_____________________________________________
3. A parotid duct is located _________________________________________________
4. The parotid glands secrete ________________________________________________
5. The submandibular glands are located ______________________________________
6. The submandibular glands secrete _________________________________________
7. Ducts of submandibular glands open _______________________________________
8. The sublingual glands are located __________________________________________
9. The sublingual glands secrete _____________________________________________
10. The ducts of sublingual glands open _______________________________________
V. Pharynx and Esophagus
A. Introduction
1. The pharynx is __________________________________________________________________________
2. The pharynx and esophagus function in ______________________________________________________
B. Structure of the Pharynx
1. The pharynx connects ___________________________________________________
2. The three divisions of the pharynx are ______________________________________
_______________________________________________________________________
3. The nasopharynx is located _______________________________________________
4. The nasopharynx provides________________________________________________
5. The oropharynx is located ________________________________________________
6. The oropharynx is a passageway for ________________________________________
7. The laryngopharynx is located ____________________________________________
8. The laryngopharynx is a passageway to _____________________________________
9. Constrictor muscles function to ____________________________________________
C. Swallowing Mechanism
1. The events of the first stage of swallowing are ________________________________
_______________________________________________________________________
2. The events of the second stage of swallowing are _____________________________
_______________________________________________________________________
3. The events of the third stage of swallowing are _______________________________
_______________________________________________________________________
4. The actions of the swallowing reflex are _____________________________________
_______________________________________________________________________
_______________________________________________________________________
D. Esophagus
1. The esophagus is a passageway for _________________________________________
2. The esophagus propels food from _______________ to the _____________________
3. The esophagus descends through __________________________________________
4. The esophageal hiatus is _________________________________________________
5. _________________ glands are scattered throughout the submucosa of the esophagus.
6. The lower esophageal sphincter is located ________________________________ and
functions to ______________________________________________________________
VII. Stomach
A. Introduction
1. The shape of the stomach is ______________________________________________
2. The location of the stomach is _____________________________________________
3. Rugae are _____________________________________________________________
4. The functions of the stomach are___________________________________________
_______________________________________________________________________
B. Parts of the Stomach
1. The four parts of the stomach are __________________________________________
2. The cardiac region is ____________________________________________________
3. The fundic region is_____________________________________________________
4. The body of the stomach is _______________________________________________
5. The pyloric region is ____________________________________________________
6. The pyloric sphincter is located_________________________________________ and
functions to ______________________________________________________________
C. Gastric Secretions
1. Gastric pits are _________________________________________________________
2. The three cell types of gastric glands are ____________________________________
_______________________________________________________________________
3. Mucous cells secrete ____________________________________________________
4. Chief cells secrete ______________________________________________________
5. Parietal cells secrete ____________________________________________________
6. Gastric juice is _________________________________________________________
7. Pepsin is______________________________________________________________
8. The function of pepsinogen is _____________________________________________
9. The function of hydrochloric acid in the stomach is ____________________________
_______________________________________________________________________
10. The coating of the stomach is important for _________________________________
_______________________________________________________________________
11. The function of intrinsic factor is _____________________________
D. Regulation of Gastric Secretions
1. Somatostatin is produced _______________________________________________________________ and
functions to _______________________________________________________________________________
2. Parasympathetic innervation stimulates _____________________________________
_______________________________________________________________________
3. Gastrin is produced __________________________________________________ and
functions to ______________________________________________________________
4. The three stages of gastric secretion are _____________________________________
_______________________________________________________________________
5. The events of the cephalic phase are ________________________________________
_______________________________________________________________________
6. The events of the gastric phase are _________________________________________
_______________________________________________________________________
7. The events of the intestinal phase are _______________________________________
_______________________________________________________________________
8. Cholecystokinin is produced ___________________________________________ and
functions to ______________________________________________________________
E. Gastric Absorption
1. The stomach absorbs ____________________________________________________
2. Most nutrients are absorbed in ____________________________________________
F. Mixing and Emptying Actions
1. A stomachache results from ______________________________________________
_______________________________________________________________________
2. Chyme is _____________________________________________________________
3. Peristaltic waves push chyme _____________________________________________
4. Stomach contractions push chyme a little at a time into ______________________ and
backwards into ____________________________________________ , mixing it further.
5. The lower esophageal sphincter prevents ____________________________________
6. The rate at which the stomach empties depends on_____________________________
_______________________________________________________________________
7. ______________________________________ usually pass first through the stomach.
8. The enterogastric reflex is ________________________________________________
_______________________________________________________________________
9. Vomiting results from ___________________________________________________
_______________________________________________________________________
VIII. Pancreas
A. Structure of the Pancreas
1. The pancreas is located __________________________________________________
_______________________________________________________________________
2. Pancreatic acinar cells produce _________________________________________ and
make up the _____________________________________________________________
3. Acini are _____________________________________________________________
4. The pancreatic ducts extends ______________________________________________
__________________________ and empties into _______________________________
5. Hepatopancreatic ampulla is ______________________________________________
6. The hepatopancreatic sphincter is __________________________________________
_______________________________________________________________________
B. Pancreatic Juice
1. Pancreatic juice contains _________________________________________________
_______________________________________________________________________
2. The function of pancreatic amylase is _______________________________________
_______________________________________________________________________
3. The function of pancreatic lipase is _________________________________________
_______________________________________________________________________
4. The functions of trypsin, chymotrypsin, and carboxypeptidase are ________________
_______________________________________________________________________
5. Zymogen granules are ___________________________________________________
6. The function of trypsinogen is_____________________________________________
7. The functions of nucleases are ____________________________________________
_______________________________________________________________________
C. Regulation of Pancreatic Secretion
1. Parasympathetic fibers cause the pancreas to _________________________________
2. The function of secretin is ________________________________________________
_______________________________________________________________________
3. The release of cholecystokinin is triggered by ________________________________
4. The action of cholecystokinin on the pancreas is ______________________________
_______________________________________________________________________
IX. Liver
A. Introduction
1. The largest internal organ is the ___________________________________________
2. The liver is located _____________________________________________________
B. Liver Structure
1. The two large lobes of the liver are _________________________________________
2. The falciform ligament is _______________________________________________ `
_______________________________________________________________________
3. The two small lobes of the liver are ________________________________________
4. The porta hepatic is _____________________________________________________
5. The coronary ligament is _________________________________________________
6. Hepatic lobules are _____________________________________________________
7. A hepatic lobule consists of_______________________________________________
_______________________________________________________________________
8. Hepatic sinusoids are ____________________________________________________
_______________________________________________________________________
9. Kupffer cells are _______________________________________________________
10. Bile canals are ________________________________________________________
11. Hepatic ducts are formed from ___________________________________________
C. Liver Functions
1. The liver carries on many important _________________________________________________ functions.
2. The liver plays a key role in carbohydrate metabolism by ________________________________________
________________________________________________________________________________________
3. The liver plays a key role in lipid metabolism by _______________________________________________
________________________________________________________________________________________
4. The liver plays a key role in protein metabolism by _____________________________________________
________________________________________________________________________________________
5. The liver stores _________________________________________________________________________
________________________________________________________________________________________
6. Liver cells help destroy ___________________________________________________________________
7. The liver removes ___________________________________________________________________ from
the blood.
8. The liver’s role in digestion is ______________________________________________________________
D. Composition of Bile
1. Bile is secreted by ______________________________________________________
2. Bile contains __________________________________________________________
3. Hepatic cells use ________________________________________ to make bile salts.
4. Bile pigments are products of _____________________________________________
5. Jaundice results from ____________________________________________________
E. Gallbladder
1. The gallbladder is located ________________________________________________
2. The cystic duct is ____________________________________________________ and
opens into _______________________________________________________________
3. The common bile duct is formed from ______________________________________
_______________________ and opens into ___________________________________
4. Gallstones form when ___________________________________________________
F. Regulation of Bile Release
1. Cholecystokinin triggers the gallbladder to ___________________________________
2. Cholecystokinin is released in response to ___________________________________
G. Functions of Bile Salts
1. Functions of bile salts are ________________________________________________
_______________________________________________________________________
2. Emulsification is _______________________________________________________
_______________________________________________________________________
3. Lack of bile salts results in _______________________________________________
X. Small Intestine
A. Introduction
1. The small intestine extends from___________________________________________
_______________________________________________________________________
2. The small intestine receives secretions from __________________________________
_______________________________________________________________________
3. The functions of the small intestine are ______________________________________
_______________________________________________________________________
B. Parts of the Small Intestine
1. The three parts of the small intestine are _____________________________________
_______________________________________________________________________
2. The duodenum is located _________________________________________________
_______________________________________________________________________
3. The jejunum is located __________________________________________________
4. The ileum is located ________________________________________
5. Mesentery is _______________________________________________________ and
supports ________________________________________________________________
6. The greater omentum is __________________________________________________
7. The functions of the omentum are __________________________________________
_______________________________________________________________________
C. Structure of the Small Intestinal Wall
1. The velvety appearance of the inner wall of the small intestine is due to _____________________________
________________________________________________________________________________________
2. Intestinal villi are _______________________________________________________
3. The functions of villi are _________________________________________________
4. Each villus consists of ___________________________________________________
_______________________________________________________________________
5. A lacteal is ____________________________________________________________
6. Microvilli increase______________________________________________________
7. Intestinal glands are _____________________________________________________
8. Plicae circulares are _____________________________________________________
_______________________________________________________________________
D. Secretions of the Small Intestine
1. Brunner’s glands are ____________________ and are located ____________________________________
________________________________________________________________________________________
2. Brunner’s glands secrete __________________________________________________________________
3. The enzymes secreted by epithelial cells of the small intestine are __________________________________
________________________________________________________________________________________
4. The functions of peptidases are _____________________________________________________________
5. The functions of sucrase, maltase, and lactase are ______________________________________________
________________________________________________________________________________________
6. The functions of intestinal lipase are _________________________________________________________
E. Regulation of the Small Intestinal Secretions
1. ____________________________________________________________________ stimulate the duodenal
mucous glands to release large amounts of mucus.
2. Chyme stimulates ______________________________________________________
3. Distension of the intestinal wall stimulates ___________________________________
_______________________________________________________________________
F. Absorption in the Small Intestine
1. The most important absorbing organ is the ___________________________________
2. Carbohydrate digestion begins _________________________________________ and
is completed _____________________________________________________________
3. Monosaccharides are absorbed by __________________________________________
_______________________________________________________________________
4. Protein digestion begins ______________________________________________ and
is complete ______________________________________________________________
5. Amino acids are absorbed by _____________________________________________
_______________________________________________________________________
6. Fat molecules are digested almost entirely by _________________________________
_______________________________________________________________________
7. Chylomicrons are ______________________________________________________
_______________________________________________________________________
8. Chylomicrons are carried to the blood by ____________________________________
9. The ions absorbed by the intestinal villi are __________________________________
_______________________________________________________________________
10. Water is absorbed by ___________________________________________________
G. Movements of the Small Intestine
1. Segmentation is ________________________________________________________
2. Chyme moves ___________________________________ through the small intestine.
3. Parasympathetics enhance __________________________________ and sympathetics
_______________________________________________________________________
4. A peristaltic rush is _____________________________________________________
5. Diarrhea results from ____________________________________________________
6. The ileocecal sphincter joins ______________________________________________
_______________________________________________________________________
XI. Large Intestine
A. Introduction
1. The large intestine is located ______________________________________________
2. The functions of the large intestine are ______________________________________
_______________________________________________________________________
B. Parts of the Large Intestine
1. The parts of the large intestine are _________________________________________
_______________________________________________________________________
2. The cecum is __________________________________________________________
3. The vermiform appendix is located ______________________________________ and
consists of _______________________________________________________________
4. The four parts of the colon are ____________________________________________
_______________________________________________________________________
5. The ascending colon is located ____________________________________________
_______________________________________________________________________
6. The transverse colon is located ____________________________________________
_______________________________________________________________________
7. The descending colon is located ___________________________________________
_______________________________________________________________________
8. The sigmoid colon is ____________________________________________________
9. The rectum is __________________________________________________________
10. The anal canal is ______________________________________________________
11. Anal columns are ______________________________________________________
12. The anus is ___________________________________________________________
13. Two sphincters of the anus are ___________________________________________
14. The internal anal sphincter is composed of __________________________________
_______________________________________________________________________
15. The external anal sphincter is composed of _________________________________
_______________________________________________________________________
C. Structure of the Large Intestinal Wall
1. Teniae coli are _________________________________________________________
2. Haustra are____________________________________________________________
3. Epiploic appendages are _________________________________________________
D. Functions of the Large Intestine
1. Mucus secretion into the large intestine is controlled by ________________________
_______________________________________________________________________
2. The functions of mucus in the large intestine are ______________________________
_______________________________________________________________________
3. Chyme entering the large intestine contains __________________________________
_______________________________________________________________________
4. The large intestine can absorb _____________________________________________
_______________________________________________________________________
5. Intestinal flora is _______________________________________________________
6. The functions of intestinal flora are_________________________________________
_______________________________________________________________________
E. Movements of the Large Intestine
1. The movements of the large intestine are _____________________________________________ than those
of the small intestine.
2. Mass movements are produced when _______________________________________
_______________________________________________________________________
3. The defecation reflex is triggered by ________________________________________
_______________________________________________________________________
4. The actions of the defecation reflex are _____________________________________
_______________________________________________________________________
5. A person can inhibit defecation by _________________________________________
F. Feces
1. Feces are composed of ___________________________________________________________________
________________________________________________________________________________________
2. The pungent odor or feces results from _______________________________________________________
_______________________________________________________________________
XII. Life-Span Changes
A. Maintaining healthy teeth requires _______________________________________________
______________________________________________________________________________
B. The effects of aging on teeth include ______________________________________________
______________________________________________________________________________
C. Dry mouths in elderly people is usually a result of ___________________________________
______________________________________________________________________________
D. Frequent heartburn may be the result of ___________________________________________
______________________________________________________________________________
E. Effects of aging on the small intestine include ______________________________________
______________________________________________________________________________
F. The effects of aging on the large intestine include ____________________________________
______________________________________________________________________________
G. The effects of aging on the pancreas, liver, and gallbladder include______________________
______________________________________________________________________________