Human Anatomy & Physiology, 9e (Marieb/Hoehn)
Chapter 23 The Digestive System
23.1 Matching Questions
Figure 23.1
Using Figure 23.1, match the following:
1) Mucosa.
Answer: A
Diff: 1 Page Ref: 855; Fig. 23.6
2) Duodenal glands found here.
Answer: B
Diff: 2 Page Ref: 855; Fig. 23.6
3) Smooth muscle layer.
Answer: C
Diff: 1 Page Ref: 855; Fig. 23.6
4) MALT found here.
Answer: B
Diff: 1 Page Ref: 855; Fig. 23.6
5) Serosa.
Answer: D
Diff: 1 Page Ref: 855; Fig. 23.6
6) Area of the lamina propria.
Answer: A
Diff: 1 Page Ref: 855; Fig. 23.6
7) Continuation of the mesentery.
Answer: D
Diff: 1 Page Ref: 855; Fig. 23.6
Figure 23.2
Using Figure 23.2, match the following:
8) Absorptive cells that line the intestinal tract.
Answer: B
Diff: 1 Page Ref: 877; Fig. 23.22
9) Cell type specialized to secrete mucus into the lumen of the intestinal tract.
Answer: D
Diff: 2 Page Ref: 877; Fig. 23.22
10) Structures that increase the absorptive area of the small intestine.
Answer: A
Diff: 2 Page Ref: 877; Fig. 23.22
11) Wide lymph capillary located in the villus.
Answer: C
Diff: 2 Page Ref: 877; Fig. 23.22
12) Paneth cells are found here.
Answer: E
Diff: 2 Page Ref: 877; Fig. 23.22
Match the following:
A)Digestion
B)Hydrolysis
C)Absorption
D) Peristalsis
13) Wavelike smooth muscle contractions that move foodstuffs through the alimentary tube.
Diff: 1 Page Ref: 851
14) Chemical or mechanical process of breaking down foodstuffs into simpler units.
Diff: 1 Page Ref: 852
15) Enzymatic breakdown of any type of food molecule.
Diff: 1 Page Ref: 892
16) Process by which simpler chemical units pass through the lumen of the gastrointestinal tract into the blood or lymph.
Diff: 1 Page Ref: 852
Answers: 13) D 14) A 15) B 16) C
Figure 23.3
Using Figure 23.3, match the following:
17) Produces enzymes that break down all categories of foodstuffs.
Answer: D
Diff: 1 Page Ref: 882; Fig. 23.1
18) Increases surface area for absorption via villi and microvilli.
Answer: B
Diff: 1 Page Ref: 875; Fig. 23.1
19) Bacteria process undigested chyme from the small intestine.
Answer: E
Diff: 2 Page Ref: 887; Fig. 23.1
20) Only digestive structure with three muscle layers.
Answer: C
Diff: 1 Page Ref: 866; Fig. 23.1
21) Receives blood via the hepatic portal system.
Answer: A
Diff: 1 Page Ref: 878; Fig. 23.1
22) Contains the brush border enzymes that complete digestion of carbohydrates and proteins.
Answer: B
Diff: 2 Page Ref: 875; Fig. 23.1
23) Main function is to filter and process the nutrient-rich blood delivered to it.
Answer: A
Diff: 1 Page Ref: 878; Fig. 23.1
24) Produces intrinsic factor.
Answer: C
Diff: 2 Page Ref: 866; Fig. 23.1
25) Produces a mucoid barrier to prevent self-digestion.
Answer: C
Diff: 3 Page Ref: 866; Fig. 23.1
Match the following:
A)Gastric Inhibitory Peptide
B)Gastrin
C) Cholecystokinin
D) Secretin
26) Increases output of enzymatic-rich pancreatic juice.
Diff: 2 Page Ref: 868; Tbl. 23.1
27) Increases output of pancreatic juice rich in bicarbonate ions.
Diff: 2 Page Ref: 868: Tbl. 23.1
28) Increases HCl secretion and stimulates contraction of intestinal muscle.
Diff: 2 Page Ref: 868; Tbl. 23.1
29) Stimulates insulin release and mildly inhibits HCl production.
Diff: 2 Page Ref: 868; Tbl. 23.1
Answers: 26) C 27) D 28) B 29) A
23.2 True/False Questions
1) The relatively unchanging pressure in a filling stomach is due to the contraction of the stomach oblique muscle layer.
Answer: FALSE
Diff: 2 Page Ref: 873
2) The circular folds of the small intestine enhance absorption by causing the chyme to spiral, rather than to move in a straight line, as it passes through the small intestine.
Answer: TRUE
Diff: 2 Page Ref: 886
3) Gastric accommodation is an example of smooth muscle plasticity.
Answer: TRUE
Diff: 3 Page Ref: 873
4) Some of the microbes that often invade other organs of the body are rarely found in the stomach. The reason for this is the presence of HCl.
Answer: TRUE
Diff: 1 Page Ref: 866
5) Stellate macrophages are found in the liver and are responsible for removing bacteria and worn-out cells.
Answer: TRUE
Diff: 1 Page Ref: 878
6) The pharyngeal-esophageal phase of swallowing is involuntary and is controlled by the swallowing center in the thalamus and lower pons.
Answer: FALSE
Diff: 1 Page Ref: 851, 864
7) All the chemical and mechanical phases of digestion from the mouth through the small intestine are directed toward changing food into forms that can pass through the epithelial cells lining the mucosa into the underlying blood and lymphatic vessels.
Answer: TRUE
Diff: 1 Page Ref: 892
8) Pepsinogen is the precursor to the gastric enzyme for protein digestion and is secreted by the parietal cells.
Answer: FALSE
Diff: 1 Page Ref: 894
9) The only essential function of the stomach is to begin the digestion of proteins.
Answer: FALSE
Diff: 2 Page Ref: 869
10) The major role of absorption in the ileum is to reclaim bile salts to be recycled back to the liver.
Answer: TRUE
Diff: 2 Page Ref: 895
11) The peritoneum is the most extensive serous membrane in the body.
Answer: TRUE
Diff: 1 Page Ref: 852
12) Peyer's patches are found in the submucosa of the distal end of the small intestine.
Answer: TRUE
Diff: 1 Page Ref: 879
13) The submucosal nerve plexus provides the major nerve supply to the GI tract wall and controls GI motility.
Answer: FALSE
Diff: 1 Page Ref: 855
14) The major means of propulsion through the alimentary canal is peristalsis.
Answer: TRUE
Diff: 1 Page Ref: 851
15) Dentin anchors the tooth in place.
Answer: FALSE
Diff: 1 Page Ref: 861
16) The digestive function of the liver is to produce bile.
Answer: TRUE
Diff: 1 Page Ref: 875
17) The pancreas has both an endocrine and an exocrine function.
Answer: TRUE
Diff: 1 Page Ref: 882-883
18) Another term for swallowing is deglutition.
Answer: TRUE
Diff: 1 Page Ref: 863
19) The intrinsic ability of visceral smooth muscle to exhibit the stress-relaxation response is termed plasticity.
Answer: TRUE
Diff: 1 Page Ref: 873
20) The stomach's contractile rhythm is set by pacemaker cells found in the spinal cord.
Answer: FALSE
Diff: 1 Page Ref: 873
21) The major stimulus for production of intestinal fluid is distention or irritation of the intestinal mucosa by hypertonic or acidic chyme.
Answer: TRUE
Diff: 2 Page Ref: 877
22) Most nutrients are absorbed through the mucosa of the intestinal villi by active transport.
Answer: TRUE
Diff: 1 Page Ref: 895-896
23) Ionic iron is actively transported into the mucosal cells, where it binds to the protein ferritin, a phenomenon called the mucosal iron barrier.
Answer: TRUE
Diff: 2 Page Ref: 898
24) Mumps is an inflammation of the parotid glands caused by myxovirus.
Answer: TRUE
Diff: 1 Page Ref: 858
25) Fats significantly delay the emptying of the stomach.
Answer: TRUE
Diff: 2 Page Ref: 874
26) The soft palate rises reflexively to open the nasopharynx when we swallow food.
Answer: FALSE
Diff: 2 Page Ref: 863
27) When swallowing, the epiglottis prevents food from entering the larynx.
Answer: TRUE
Diff: 2 Page Ref: 863-4; Fig 23.13
28) Most gastric ulcers are due to excessive production of hydrochloric acid.
Answer: FALSE
Diff: 2 Page Ref: 869
23.3 Multiple-Choice Questions
1) The mechanical and chemical receptors that control digestive activity are located ______.
A) in the glandular tissue that lines the organ lumen
B) in the walls of the tract organs
C) in the pons and medulla
D) in the oral cavity
Answer: B
Diff: 1 Page Ref: 852
2) The function of the hepatic portal circulation is to ______.
A) carry toxins to the venous system for disposal through the urinary tract
B) collect absorbed nutrients for metabolic processing or storage
C) distribute hormones throughout the body
D) return glucose to the general circulation when blood sugar is low
Answer: B
Diff: 1 Page Ref: 878-881
3) The chemical and mechanical processes of food breakdown are called ______.
A) digestion
B) absorption
C) ingestion
D) secretion
Answer: A
Diff: 1 Page Ref: 850-851
4) When we ingest large molecules such as lipids, carbohydrates, and proteins, they must undergo catabolic reactions whereby enzymes split these molecules. This series of reactions is called ______.
A) absorption
B) secretion
C) chemical digestion
D) mechanical digestion
Answer: C
Diff: 1 Page Ref: 852
5) The sheets of peritoneal membrane that hold the digestive tract in place are called ______.
A) mesenteries
B) lamina propria
C) serosal lining
D) mucosal lining
Answer: A
Diff: 1 Page Ref: 852
6) From the esophagus to the anal canal, the walls of every organ of the alimentary canal are made up of the same four basic layers. Arrange them in order from the lumen.
A) muscularis externa, serosa, mucosa, and submucosa
B) serosa, mucosa, submucosa, and muscularis externa
C) submucosa, serosa, muscularis externa, and mucosa
D) mucosa, submucosa, muscularis externa, and serosa
Answer: D
Diff: 1 Page Ref: 854-855
7) Which of the following is not a factor that helps create the stomach mucosal barrier?
A) thick coating of bicarbonate-rich mucus
B) tight junctions of epithelial mucosa cells
C) replacing of damaged epithelial mucosa cells
D) production of intrinsic factor
Answer: D
Diff: 2 Page Ref: 867-868
8) What part of the tooth bears the force of chewing?
A) crown
B) enamel
C) pulp
D) cementum
Answer: B
Diff: 1 Page Ref: 860
9) The capillaries that nourish the epithelium and absorb digested nutrients lie in the ______.
A) submucosa
B) serosa
C) adventitia
D) lamina propria
Answer: D
Diff: 1 Page Ref: 855
10) Which hormone causes an increased output of enzyme-rich pancreatic juice and stimulates gallbladder contraction to release bile?
A) gastrin
B) secretin
C) cholecystokinin
D) gastric inhibitor peptide
Answer: C
Diff: 1 Page Ref: 883
11) Choose the incorrect statement regarding bile.
A) Bile is both an excretory product and a digestive secretion.
B) Bile functions to emulsify fats.
C) Bile functions to carry bilirubin formed from breakdown of worn-out RBCs.
D) Bile contains enzymes for digestion.
Answer: D
Diff: 1 Page Ref: 881
12) The absorptive effectiveness of the small intestine is enhanced by increasing the surface area of the mucosal lining. Which of the following accomplish this task?
A) plicae circulares, villi, and microvilli
B) the vast array of digestive enzymes
C) Brunner's glands and Peyer Patches
D) the rugae and haustra
Answer: A
Diff: 1 Page Ref: 876
13) Select the statement that is true concerning primary teeth.
A) There are 27 primary teeth, and the molars are permanent.
B) There are 24 primary teeth, and no new primary teeth appear after 13 months.
C) There are 20 primary teeth, and by 24 months of age most children have all 20.
D) There are 32 primary teeth, and by 36 months of age, most children have all 32.
Answer: C
Diff: 1 Page Ref: 859-860
14) Which of the following is true concerning the number and type of permanent teeth?
A) There are 32 permanent teeth, and the wisdom teeth are the last to emerge.
B) There are 27 permanent teeth, and the first molars are usually the last to emerge.
C) The number of permanent teeth is always equal to the number of primary teeth.
D) The number of upper permanent teeth is not equal to the number of lower permanent teeth.
Answer: A
Diff: 1 Page Ref: 860
15) Which of the following is not true of saliva?
A) cleanses the mouth
B) contains enzymes that begin the breakdown of proteins
C) moistens food and aids in compacting of the bolus
D) dissolves food chemicals so they can be tasted
Answer: B
Diff: 1 Page Ref: 858
16) The salivary glands are composed of which two types of secretory cells?
A) goblet cells and squamous epithelial cells
B) parietal cells and glial cells
C) serous cells and mucous cells
D) cuboidal epithelium and ciliated columnar cells
Answer: C
Diff: 1 Page Ref: 858
17) The solutes contained in saliva include ______.
A) only salts and minerals
B) only proteases and amylase
C) mucin, lysozyme, electrolytes, salts, and minerals
D) electrolytes, digestive enzyme, mucin, lysozyme, wastes, and IgA
Answer: D
Diff: 1 Page Ref: 859
18) In addition to storage and mechanical breakdown of food, the stomach ______.
A) initiates protein digestion and denatures proteins
B) is the first site where absorption takes place
C) is the only place where fats are completely digested
D) is the first site where chemical digestion of starch takes place
Answer: A
Diff: 1 Page Ref: 864, 869-870
9) Chyme is created in the ______.
A) mouth
B) stomach
C) esophagus
D) small intestine
Answer: B
Diff: 1 Page Ref: 864
20) Hydrochloric acid is secreted by which of the secretory cells of the stomach?
A) chief cells
B) parietal cells
C) serous cells
D) mucous neck cells
Answer: B
Diff: 1 Page Ref: 866
21) Gastrin, histamine, endorphins, serotonin, cholecystokinin, and somatostatin are hormones or paracrines that are released directly into the lamina propria. Which of the following cell types synthesize and secrete these products?
A) enteroendocrine cells
B) parietal cells
C) zymogenic cells
D) mucous neck cells
Answer: A
Diff: 1 Page Ref: 866-867
22) There are three phases of gastric secretion. The cephalic phase occurs ______.
A) before food enters the stomach and is triggered by aroma, sight, or thought
B) immediately after food enters the stomach, preparing the small intestine for the influx of a variety of nutrients
C) at the end of a large meal, and the juices secreted are powerful and remain in the GI tract for a long period of time
D) when the meal is excessively high in acids and neutralization is required
Answer: A
Diff: 1 Page Ref: 870
23) Peristaltic waves are ______.
A) segmental regions of the gastrointestinal tract
B) churning movements of the gastrointestinal tract
C) pendular movements of the gastrointestinal tract
D) waves of muscular contractions that propel contents from one point to another
Answer: D
Diff: 1 Page Ref: 851
24) Gastrin is a digestive hormone that is responsible for the stimulation of acid secretions in the stomach. These secretions are stimulated by the presence of ______.
A) starches and complex carbohydrates
B) protein and peptide fragments
C) simple carbohydrates and alcohols
D) fatty acids
Answer: B
Diff: 1 Page Ref: 870
25) Pepsinogen, a digestive enzyme, is secreted by the ______.
A) chief cells of the stomach
B) parietal cells of the duodenum
C) Brunner's glands
D) goblet cells of the small intestine
Answer: A
Diff: 1 Page Ref: 866
26) You have just eaten a meal high in complex carbohydrates. Which of the following enzymes will help to digest the meal?
A) gastrin
B) amylase
C) cholecystokinin
D) trypsin
Answer: B
Diff: 1 Page Ref: 892
27) The ducts that deliver bile and pancreatic juice from the liver and pancreas, respectively, unite to form the ______.
A) portal vein
B) pancreatic acini
C) bile canaliculus
D) hepatopancreatic ampulla
Answer: D
Diff: 1 Page Ref: 883
28) The enzymatic breakdown of any type of food molecule is called ______.
A) diffusion
B) active transport
C) hydrolysis
D) denatured
Answer: C
Diff: 1 Page Ref: 892
29) Short-chain triglycerides found in foods such as butterfat molecules in milk are split by a specific enzyme in preparation for absorption. Which of the following enzymes is responsible?
A) rennin
B) pepsin
C) lipase
D) cholecystokinin
Answer: C
Diff: 1 Page Ref: 895
30) Parietal cells of the stomach produce ______.
A) mucin
B) pepsinogen
C) hydrochloric acid
D) rennin
Answer: C
Diff: 1 Page Ref: 866
31) Hepatocytes do not ______.
A) produce digestive enzymes
B) process nutrients
C) store fat-soluble vitamins
D) detoxify toxic chemicals
Answer: A
Diff: 1 Page Ref: 878
32) Which of the following is not a phase of gastric secretion?
A) cephalic
B) gastric
C) intestinal
D) enterogastric
Answer: D
Diff: 1 Page Ref: 870-872
33) Which vitamin requires intrinsic factor in order to be absorbed?
A) B12
B) K
C) A
D) C
Answer: A
Diff: 2 Page Ref: 870
34) Chief cells ______.
A) produce gastrin
B) produce HCl
C) produce pepsinogen
D) produce mucin
Answer: C
Diff: 1 Page Ref: 866
35) Chemical digestion reduces large complex molecules to simpler compounds by the process of ______.
A) mastication
B) catabolism
C) anabolism
D) fermentation
Answer: B
Diff: 1 Page Ref: 852
36) The ______contains lobules with sinusoids (lined with macrophages) that lead to a central venous structure.
A) liver
B) spleen
C) pancreas
D) stomach
Answer: A
Diff: 1 Page Ref: 878
37) If an incision has to be made in the small intestine to remove an obstruction, the first layer of tissue to be cut is the ______.
A) serosa
B) mucosa
C) muscularis externa
D) submucosa
Answer: A
Diff: 1 Page Ref: 855
38) Digestion of which of the following would be affected the most if the liver were severely damaged?
A) lipids
B) carbohydrates
C) proteins
D) starches
Answer: A
Diff: 2 Page Ref: 878
39) The dental formula for an adult is 2-1-2-3. What does the 1 stand for?
A) incisor tooth
B) molar tooth
C) premolar tooth
D) canine tooth
Answer: D
Diff: 2 Page Ref: 860
40) The lamina propria is composed of ______.
A) loose connective tissue
B) dense irregular connective tissue
C) dense regular connective tissue
D) reticular connective tissue
Answer: A
Diff: 1 Page Ref: 855
41) Which of the following is (are) not important as a stimulus in the gastric phase of gastric secretion?
A) distention
B) carbohydrates
C) peptides
D) low acidity
Answer: B
Diff: 1 Page Ref: 870-871
42) The function of goblet cells is to ______.
A) absorb nutrients from digested food and store them for future use
B) produce mucus that protects parts of the digestive organs from the effects of powerful enzymes needed for food digestion
C) secrete buffers in order to keep the pH of the digestive tract close to neutral
D) provide protection against invading bacteria and other disease-causing organisms that enter the digestive tract in food
Answer: B
Diff: 2 Page Ref: 877
43) Which of the following is an essential role played by large intestine bacteria?
A) produce gas
B) absorb bilirubin
C) synthesize vitamin K and B-complex vitamins
D) synthesize vitamins C and D
Answer: C
Diff: 1 Page Ref: 890
44) Nervous control of gastric secretion is provided by ______.
A) somatic neurons in the spinal cord
B) the vagus nerve and enteric plexus
C) the rubrospinal tracts
D) the reticulospinal and vestibulospinal tracts
Answer: B
Diff: 2 Page Ref: 870
45) Which of the following are types of papillae on the tongue that contain taste buds?