,BIOD 121 Module 2 Exam | Essentials in
Nutrition | Portage Learning | Q & A 2026
Edition
1. Which of the following best defines digestion?
A) The process of absorbing nutrients into the bloodstream
B) The process of transforming food into basic nutrients that can be absorbed and used by the body
C) The mechanical breakdown of food into smaller pieces
D) The elimination of undigested waste from the body
Correct Answer: The process of transforming food into basic nutrients that can be absorbed and used by
the body
Rationale: Digestion is the process that breaks down food into its basic components so they can be
absorbed and utilized by the body. It encompasses both mechanical and chemical processes. Absorption
is a separate step, and elimination is the final stage of the digestive process.
2. What are the six major parts of the gastrointestinal (GI) tract as outlined by the module?
A) Mouth, esophagus, stomach, small intestine, large intestine, and rectum
B) Mouth, pharynx, stomach, small intestine, colon, and anus
C) Esophagus, stomach, liver, gallbladder, pancreas, and small intestine
D) Mouth, esophagus, stomach, pancreas, large intestine, and rectum
Correct Answer: Mouth, esophagus, stomach, small intestine, large intestine, and rectum
Rationale: The GI tract is a continuous tube consisting of the mouth, esophagus, stomach, small
intestine, large intestine, and rectum. The liver, gallbladder, and pancreas are accessory organs that aid
in digestion but are not part of the GI tract itself.
3. Which of the following are considered accessory organs of the digestive system?
,A) Mouth, esophagus, and stomach
B) Small intestine, large intestine, and rectum
C) Salivary glands, liver, gallbladder, and pancreas
D) Pancreas, stomach, and small intestine
Correct Answer: Salivary glands, liver, gallbladder, and pancreas
Rationale: Accessory organs assist in digestion but are not part of the GI tract. They include the salivary
glands, liver, gallbladder, and pancreas. The mouth, esophagus, stomach, and intestines are part of the
GI tract.
4. What is the primary role of saliva in digestion?
A) To break down proteins into amino acids
B) To lubricate food particles and begin starch digestion
C) To emulsify fats for easier absorption
D) To neutralize stomach acid before it reaches the intestines
Correct Answer: To lubricate food particles and begin starch digestion
Rationale: Saliva contains mucus for lubrication and the enzyme salivary amylase, which begins the
chemical digestion of starch. Protein digestion begins in the stomach, and fat emulsification is a function
of bile.
5. Which enzyme found in saliva is responsible for breaking down starch?
A) Lingual lipase
B) Pepsin
C) Salivary amylase
D) Trypsin
Correct Answer: Salivary amylase
, Rationale: Salivary amylase is an enzyme in saliva that initiates the breakdown of starch into smaller
sugars. Lingual lipase begins fat digestion, pepsin works in the stomach on proteins, and trypsin acts in
the small intestine.
6. What is the function of the esophageal sphincter?
A) To regulate the entry of food into the stomach
B) To prevent the contents of the stomach from reentering the esophagus
C) To control the release of bile from the gallbladder
D) To separate the small intestine from the large intestine
Correct Answer: To prevent the contents of the stomach from reentering the esophagus
Rationale: The esophageal (cardiac) sphincter prevents stomach contents from flowing back into the
esophagus, which would cause heartburn. The pyloric sphincter regulates entry into the small intestine.
7. A student is studying the wave-like muscle contractions that propel food through the digestive
system. What process is being observed?
A) Segmentation
B) Peristalsis
C) Mastication
D) Deglutition
Correct Answer: Peristalsis
Rationale: Peristalsis refers to the involuntary wave-like muscle contractions that move food in one
direction through the digestive tract. Segmentation is a mixing movement, mastication is chewing, and
deglutition is swallowing.
8. What is the primary function of the stomach in the digestive process?
A) To absorb most nutrients from food
Nutrition | Portage Learning | Q & A 2026
Edition
1. Which of the following best defines digestion?
A) The process of absorbing nutrients into the bloodstream
B) The process of transforming food into basic nutrients that can be absorbed and used by the body
C) The mechanical breakdown of food into smaller pieces
D) The elimination of undigested waste from the body
Correct Answer: The process of transforming food into basic nutrients that can be absorbed and used by
the body
Rationale: Digestion is the process that breaks down food into its basic components so they can be
absorbed and utilized by the body. It encompasses both mechanical and chemical processes. Absorption
is a separate step, and elimination is the final stage of the digestive process.
2. What are the six major parts of the gastrointestinal (GI) tract as outlined by the module?
A) Mouth, esophagus, stomach, small intestine, large intestine, and rectum
B) Mouth, pharynx, stomach, small intestine, colon, and anus
C) Esophagus, stomach, liver, gallbladder, pancreas, and small intestine
D) Mouth, esophagus, stomach, pancreas, large intestine, and rectum
Correct Answer: Mouth, esophagus, stomach, small intestine, large intestine, and rectum
Rationale: The GI tract is a continuous tube consisting of the mouth, esophagus, stomach, small
intestine, large intestine, and rectum. The liver, gallbladder, and pancreas are accessory organs that aid
in digestion but are not part of the GI tract itself.
3. Which of the following are considered accessory organs of the digestive system?
,A) Mouth, esophagus, and stomach
B) Small intestine, large intestine, and rectum
C) Salivary glands, liver, gallbladder, and pancreas
D) Pancreas, stomach, and small intestine
Correct Answer: Salivary glands, liver, gallbladder, and pancreas
Rationale: Accessory organs assist in digestion but are not part of the GI tract. They include the salivary
glands, liver, gallbladder, and pancreas. The mouth, esophagus, stomach, and intestines are part of the
GI tract.
4. What is the primary role of saliva in digestion?
A) To break down proteins into amino acids
B) To lubricate food particles and begin starch digestion
C) To emulsify fats for easier absorption
D) To neutralize stomach acid before it reaches the intestines
Correct Answer: To lubricate food particles and begin starch digestion
Rationale: Saliva contains mucus for lubrication and the enzyme salivary amylase, which begins the
chemical digestion of starch. Protein digestion begins in the stomach, and fat emulsification is a function
of bile.
5. Which enzyme found in saliva is responsible for breaking down starch?
A) Lingual lipase
B) Pepsin
C) Salivary amylase
D) Trypsin
Correct Answer: Salivary amylase
, Rationale: Salivary amylase is an enzyme in saliva that initiates the breakdown of starch into smaller
sugars. Lingual lipase begins fat digestion, pepsin works in the stomach on proteins, and trypsin acts in
the small intestine.
6. What is the function of the esophageal sphincter?
A) To regulate the entry of food into the stomach
B) To prevent the contents of the stomach from reentering the esophagus
C) To control the release of bile from the gallbladder
D) To separate the small intestine from the large intestine
Correct Answer: To prevent the contents of the stomach from reentering the esophagus
Rationale: The esophageal (cardiac) sphincter prevents stomach contents from flowing back into the
esophagus, which would cause heartburn. The pyloric sphincter regulates entry into the small intestine.
7. A student is studying the wave-like muscle contractions that propel food through the digestive
system. What process is being observed?
A) Segmentation
B) Peristalsis
C) Mastication
D) Deglutition
Correct Answer: Peristalsis
Rationale: Peristalsis refers to the involuntary wave-like muscle contractions that move food in one
direction through the digestive tract. Segmentation is a mixing movement, mastication is chewing, and
deglutition is swallowing.
8. What is the primary function of the stomach in the digestive process?
A) To absorb most nutrients from food
