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Campbell Essential Biology, 6e (Simon/Dickey/Hogan/Reece)
Chapter 22 Nutrition and Digestion
Chapter 22 Learning Outcomes
22 Biology and Society: The “Secret” to Shedding Pounds
22.1. Explain why there are really no tricks to losing weight.
22.1 An Overview of Animal Nutrition
22.2. Define and distinguish between different types of animal diets.
22.3. List and describe the general steps involved in digestion, and explain how and why
mechanical and chemical digestion dismantles large food molecules.
22.4. Describe the structure and functions of different types of digestive compartments.
22.2 A Tour of the Human Digestive System
22.5. Describe the structure and function of the main components of the human digestive tract
and the associated digestive glands.
22.6. Describe the causes and treatments of disorders of the human digestive system.
22.3 Human Nutritional Requirements
22.7. Explain how energy in food is measured, and how metabolic activity results in weight
loss or gain.
22.8. List and define essential components of the human diet, and describe how deficiencies in
these components can lead to health problems.
22.9. Describe the types of information found on food labels.
22.4 Nutritional Disorders
22.10. Describe the causes and treatments of different nutritional disorders.
22 Evolution Connection: Fat and Sugar Cravings
22.11. Explain how cravings for fat might have evolved in humans.
Global Learning Outcomes
1. Demonstrate an understanding of the principles of scientific inquiry.
2. Demonstrate the ability to think critically and employ critical-thinking skills.
3. Read and interpret models, graphs, and data.
4. Demonstrate the quantitative skills needed to succeed in biology.
5. Demonstrate an understanding of the impact of science on society.
6. Evaluate the credibility of scientific information from various sources.
7. Demonstrate the ability to make connections between concepts across biology.
8. Communicate effectively in writing.
9. Apply the scientific method to interpret information and draw conclusions.
22.1 Multiple Choice Questions
1) Spiders are ________.
A) herbivores
B) filter feeders
C) carnivores
D) omnivores
2) Digestion is ________.
A) the absorption of nutrients
B) the breakdown of food into small nutrient molecules that the body can absorb
C) the churning of food in the stomach and intestine
D) eating
3) The four stages of food processing are, in order ________.
A) ingestion, absorption, elimination, digestion
B) ingestion, elimination, digestion, absorption
C) ingestion, digestion, absorption, elimination
D) digestion, absorption, ingestion, elimination
4) Which of the following is an example of mechanical digestion?
A) the breakdown of proteins into amino acids
B) peristalsis
C) the digestion of fats by lipases
D) chewing
5) The digestive sac of a jellyfish has ________ opening(s).
A) one
B) two
C) three
D) four
6) A digestive tube is best defined as ________.
A) the compartment in which an animal digests its food
B) a tube-shaped digestive compartment with either one or two openings
C) a tube-shaped digestive compartment that has two openings and through which food moves in
one direction
D) a digestive compartment that conducts both chemical and mechanical digestion
7) The main function of salivary amylase is to ________.
A) moisten food
B) break down proteins
C) absorb nutrients
D) break down starch
8) Which of the following choices lists the organs of the human alimentary canal in the
CORRECT order?
A) pharynx, oral cavity, esophagus, stomach, large intestine
B) oral cavity, pharynx, esophagus, stomach, small intestine, large intestine
C) esophagus, pharynx, stomach, large intestine, small intestine
D) oral cavity, esophagus, stomach, large intestine, small intestine
9) Digestion begins in the ________.
A) oral cavity
B) esophagus
C) pharynx
D) stomach
10) The tongue does all of the following EXCEPT ________.
A) taste food
B) shape food into a ball
C) secrete saliva
D) push food into the pharynx
11) Muscular contraction moves food through the alimentary canal by a process called
________.
A) propulsion
B) active transport
C) peristalsis
D) swallowing
12) What is the epiglottis?
A) a muscle that moves the esophagus into line with the pharynx during swallowing
B) a muscle that moves the trachea out of line with the pharynx during swallowing
C) a flap that flips down to cover the entry to the trachea during swallowing
D) a muscular sphincter that closes off the entry to the trachea during swallowing
13) The esophagus and trachea are both open to the ________.
A) pharynx
B) posterior oral cavity
C) posterior nasal cavity
D) larynx
14) A food ball moves through the esophagus by ________.
A) peristalsis
B) gastric juice
C) mastication
D) regurgitation
15) The stomach’s gastric juice consists of ________.
A) digestive enzymes only
B) hydrochloric acid only
C) digestive enzymes and hydrochloric acid only
D) mucus, digestive enzymes, and hydrochloric acid
16) When contracted, ________ prevents movement of chyme from the stomach to the small
intestine.
A) peristalsis
B) reverse peristalsis
C) the epiglottis
D) a sphincter
17) Which of the following is the usual cause of heartburn?
A) backflow of chyme from the stomach into the esophagus
B) retention of food at the bottom of the esophagus by a sphincter that is reluctant to open
C) irritation of the lower esophagus by substances in spicy food
D) compression of the lower esophagus by an overfilled stomach
18) Which of the following mechanisms helps prevent gastric juice from digesting the stomach
lining?
A) mucus coating the inside surface of the stomach
B) contractions of the stomach constantly moving chyme into the small intestine
C) the continuous secretion of gastric juice
D) the inactivation of pepsin by hydrochloric acid
19) The stomach mixes food with the secretions of the stomach wall to form ________.
A) gastric juice
B) a food ball
C) chyme
D) acid gastrin
20) When the wall of the stomach fails to protect itself from erosion by gastric juice, the result is
________.
A) heartburn
B) obesity
C) GERD
D) a gastric ulcer
21) How does Helicobacter pylori cause gastric ulcers in humans?
A) It neutralizes the acids of the stomach.
B) It causes the production of excess acid in the stomach.
C) It damages the stomach’s mucus coat.
D) It causes the stomach to produce stronger acids.
22) Most nutrient absorption occurs in which part of the digestive system?
A) stomach
B) duodenum
C) the several meters of the small intestine that come after the duodenum
D) large intestine
23) Bile from the liver is stored in the ________ before entering the intestine.
A) pancreas
B) gallbladder
C) large intestine
D) bile duct
24) What is the main digestive function of the pancreas?
A) It produces digestive enzymes and bile.
B) It produces bile.
C) It produces digestive enzymes and neutralizes stomach acids.
D) It secretes mucus into the small intestine.
25) Someone with liver failure will, in particular, have problems with the digestion and
absorption of ________.
A) minerals
B) fats
C) carbohydrates
D) proteins
26) Which of the following nutrients begins undergoing chemical digestion in the mouth?
A) amino acids
B) protein
C) starch
D) glucose
27) The epithelial cells lining the intestine have surface projections that increase the area for
absorption. These projections are called ________.
A) villi
B) mucus
C) microvilli
D) bile
28) Together with the small intestine, the ________ absorbs water.
A) stomach
B) colon
C) rectum
D) appendix
29) Altogether, the body secretes about 7 liters of water into the alimentary canal each day.
About what percentage of this water gets reabsorbed?
A) 30%
B) 50%
C) 60%
D) 90%
30) Which structure stores feces until they can be eliminated?
A) rectum
B) appendix
C) anus
D) colon
31) ________ the direct source of energy for cells.
A) Fats are
B) Glucose is
C) ATP is
D) Amino acids are
32) Most humans need about ________ kcal per day.
A) 500-700
B) 1,300-1,800
C) 2,500-3,000
D) 20,000-30,000
33) Your metabolic rate depends on ________.
I) your age
II) your activity levels
III) genetics
A) I only
B) I and II, but not III
C) II only
D) I, II, and III
34) Humans need food in order to obtain ________.
I) essential nutrients
II) fuel to power all body activities
III) organic raw materials to make their own molecules
A) I only
B) I and II, but not III
C) II only
D) I, II, and III
35) Vitamins are ________.
A) organic molecules that are required in the diet in very small amounts
B) nutrients that we can synthesize from simpler molecules
C) important supplements for children, but not adults
D) required to synthesize most amino acids
36) Certain amino acids are called essential because they ________.
A) are required for making protein
B) cannot be made by the body from other compounds
C) store energy
D) are required for making nucleic acids
37) Which mineral is needed for the proper functioning of nerves, muscles, and bones?
A) calcium
B) linoleic acid
C) sodium
D) salt
38) What do the vitamins biotin and Vitamin K have in common?
A) They are both water-soluble vitamins.
B) They are both obtained from meat.
C) They are both produced by intestinal bacteria.
D) They are both common deficiencies in the human diet.
39) On a global scale, the most significant type of malnutrition is ________.
A) vitamin A deficiency
B) calcium deficiency
C) iron deficiency
D) protein deficiency