BIOL 121 | BIOL121 Module 8: Nutrition Updated
and Latest Questions and Correct Answers with
Rationale - Portage Learning
1. Which enzyme is primarily responsible for the initial chemical digestion of carbohydrates in
the mouth?
A. Pepsin
B. Pancreatic lipase
C. Salivary amylase
D. Trypsin
Correct Answer: C
Expert Explanation: Chemical digestion begins in the mouth with the secretion of salivary
amylase. This enzyme specifically targets the breakdown of complex starches into simpler
sugars like maltose. Mechanical digestion via chewing supports this process by increasing
the food’s surface area. Without this initial step, the subsequent enzymatic actions in the
small intestine would be less efficient. Thus, the mouth serves as the critical entry point for
carbohydrate metabolism.
2. A patient has had their gallbladder removed (cholecystectomy). Which macronutrient will
they have the most difficulty digesting?
A. Fats
B. Complex carbohydrates
C. Proteins
D. Simple sugars
Correct Answer: A
Expert Explanation: The gallbladder stores and concentrates bile produced by the liver.
Bile is essential for the emulsification of dietary fats in the small intestine. Emulsification
breaks large fat globules into smaller droplets to allow lipase to work effectively. After a
cholecystectomy, the continuous drip of bile from the liver is less effective at handling high-
fat meals. Therefore, patients must often limit fat intake to avoid digestive distress and
malabsorption.
3. Which of the following describes the primary site of nutrient absorption in the human
body?
A. The stomach
B. The large intestine
,C. The small intestine
D. The esophagus
Correct Answer: C
Expert Explanation: The small intestine is the principal organ for the absorption of
nutrients into the bloodstream. Its internal surface is covered with villi and microvilli
which dramatically increase the surface area. This vast area allows for the efficient
transport of glucose, amino acids, and fatty acids. While the stomach starts protein
digestion, very little absorption occurs there. Consequently, the small intestine is vital for
extracting energy and building blocks from our diet.
4. Which process describes the breakdown of complex molecules into smaller ones to release
energy?
A. Anabolism
B. Catabolism
C. Photosynthesis
D. Emulsification
Correct Answer: B
Expert Explanation: Catabolism involves metabolic pathways that break down larger
molecules like glucose or lipids into smaller units. This process is generally exergonic,
meaning it releases energy used to form ATP. In contrast, anabolism uses energy to build
complex structures like muscle tissue. Both processes must be balanced to maintain
cellular homeostasis and overall health. Understanding catabolism helps explain how the
body fuels daily activities and physiological functions.
5. What is the function of hydrochloric acid (HCl) in the gastric juice of the stomach?
A. To digest starch into glucose
B. To emulsify fats for absorption
C. To denature proteins and activate pepsin
D. To neutralize the acidity of chyme
Correct Answer: C
Expert Explanation: Hydrochloric acid creates a highly acidic environment in the stomach
which is necessary for protein digestion. This acidity causes proteins to denature or unfold,
making them easier for enzymes to access. HCl also converts the inactive enzyme
pepsinogen into its active form, pepsin. Additionally, the low pH helps kill many harmful
bacteria ingested with food. This chemical environment is essential for the transition from
the bolus to semi-liquid chyme.
, 6. Water-soluble nutrients, such as Vitamin C and B-vitamins, are transported from the small
intestine to which organ first?
A. The heart
B. The lungs
C. The kidneys
D. The liver
Correct Answer: D
Expert Explanation: Water-soluble nutrients are absorbed directly into the capillaries of
the villi in the small intestine. These capillaries drain into the hepatic portal vein, which
carries the blood directly to the liver. The liver then processes these nutrients, storing
some and releasing others into the general circulation. This ‘first pass’ allows the liver to
detoxify substances and regulate blood nutrient levels. It ensures that the rest of the body
receives a balanced supply of essential vitamins.
7. A person with Celiac disease experiences damage to the intestinal villi. What is the most
likely nutritional consequence?
A. Malabsorption of multiple nutrients
B. Increased rate of glucose absorption
C. Excessive storage of fat-soluble vitamins
D. Enhanced protein synthesis
Correct Answer: A
Expert Explanation: Celiac disease is an autoimmune reaction to gluten that causes the
flattening of the intestinal villi. Since villi are responsible for nutrient absorption, their
destruction leads to a significant decrease in available surface area. This results in the
malabsorption of fats, proteins, carbohydrates, and micronutrients. Patients often suffer
from deficiencies, weight loss, and fatigue due to this impaired uptake. Maintaining a
gluten-free diet is the primary treatment to allow the villi to heal.
8. Where is the majority of the body’s glycogen stored for quick energy release?
A. Liver and skeletal muscles
B. Pancreas and kidneys
C. Adipose tissue and brain
D. Stomach and small intestine
Correct Answer: A
and Latest Questions and Correct Answers with
Rationale - Portage Learning
1. Which enzyme is primarily responsible for the initial chemical digestion of carbohydrates in
the mouth?
A. Pepsin
B. Pancreatic lipase
C. Salivary amylase
D. Trypsin
Correct Answer: C
Expert Explanation: Chemical digestion begins in the mouth with the secretion of salivary
amylase. This enzyme specifically targets the breakdown of complex starches into simpler
sugars like maltose. Mechanical digestion via chewing supports this process by increasing
the food’s surface area. Without this initial step, the subsequent enzymatic actions in the
small intestine would be less efficient. Thus, the mouth serves as the critical entry point for
carbohydrate metabolism.
2. A patient has had their gallbladder removed (cholecystectomy). Which macronutrient will
they have the most difficulty digesting?
A. Fats
B. Complex carbohydrates
C. Proteins
D. Simple sugars
Correct Answer: A
Expert Explanation: The gallbladder stores and concentrates bile produced by the liver.
Bile is essential for the emulsification of dietary fats in the small intestine. Emulsification
breaks large fat globules into smaller droplets to allow lipase to work effectively. After a
cholecystectomy, the continuous drip of bile from the liver is less effective at handling high-
fat meals. Therefore, patients must often limit fat intake to avoid digestive distress and
malabsorption.
3. Which of the following describes the primary site of nutrient absorption in the human
body?
A. The stomach
B. The large intestine
,C. The small intestine
D. The esophagus
Correct Answer: C
Expert Explanation: The small intestine is the principal organ for the absorption of
nutrients into the bloodstream. Its internal surface is covered with villi and microvilli
which dramatically increase the surface area. This vast area allows for the efficient
transport of glucose, amino acids, and fatty acids. While the stomach starts protein
digestion, very little absorption occurs there. Consequently, the small intestine is vital for
extracting energy and building blocks from our diet.
4. Which process describes the breakdown of complex molecules into smaller ones to release
energy?
A. Anabolism
B. Catabolism
C. Photosynthesis
D. Emulsification
Correct Answer: B
Expert Explanation: Catabolism involves metabolic pathways that break down larger
molecules like glucose or lipids into smaller units. This process is generally exergonic,
meaning it releases energy used to form ATP. In contrast, anabolism uses energy to build
complex structures like muscle tissue. Both processes must be balanced to maintain
cellular homeostasis and overall health. Understanding catabolism helps explain how the
body fuels daily activities and physiological functions.
5. What is the function of hydrochloric acid (HCl) in the gastric juice of the stomach?
A. To digest starch into glucose
B. To emulsify fats for absorption
C. To denature proteins and activate pepsin
D. To neutralize the acidity of chyme
Correct Answer: C
Expert Explanation: Hydrochloric acid creates a highly acidic environment in the stomach
which is necessary for protein digestion. This acidity causes proteins to denature or unfold,
making them easier for enzymes to access. HCl also converts the inactive enzyme
pepsinogen into its active form, pepsin. Additionally, the low pH helps kill many harmful
bacteria ingested with food. This chemical environment is essential for the transition from
the bolus to semi-liquid chyme.
, 6. Water-soluble nutrients, such as Vitamin C and B-vitamins, are transported from the small
intestine to which organ first?
A. The heart
B. The lungs
C. The kidneys
D. The liver
Correct Answer: D
Expert Explanation: Water-soluble nutrients are absorbed directly into the capillaries of
the villi in the small intestine. These capillaries drain into the hepatic portal vein, which
carries the blood directly to the liver. The liver then processes these nutrients, storing
some and releasing others into the general circulation. This ‘first pass’ allows the liver to
detoxify substances and regulate blood nutrient levels. It ensures that the rest of the body
receives a balanced supply of essential vitamins.
7. A person with Celiac disease experiences damage to the intestinal villi. What is the most
likely nutritional consequence?
A. Malabsorption of multiple nutrients
B. Increased rate of glucose absorption
C. Excessive storage of fat-soluble vitamins
D. Enhanced protein synthesis
Correct Answer: A
Expert Explanation: Celiac disease is an autoimmune reaction to gluten that causes the
flattening of the intestinal villi. Since villi are responsible for nutrient absorption, their
destruction leads to a significant decrease in available surface area. This results in the
malabsorption of fats, proteins, carbohydrates, and micronutrients. Patients often suffer
from deficiencies, weight loss, and fatigue due to this impaired uptake. Maintaining a
gluten-free diet is the primary treatment to allow the villi to heal.
8. Where is the majority of the body’s glycogen stored for quick energy release?
A. Liver and skeletal muscles
B. Pancreas and kidneys
C. Adipose tissue and brain
D. Stomach and small intestine
Correct Answer: A
