WGU D440 Nutrition OA Exam – Complete Study Guide (2026/2027)
Practice Questions 1–200
Section 1: Nutrition Science Foundations (Questions 1–20)
1. Which of the following best describes the primary objective of nutritional
science as defined for the WGU D440 course? - A) The study of food
processing techniques and packaging methods for commercial distribution. -
B) The intake of food, considered in relation to the body's dietary needs and
its effects on health. - C) The practice of eliminating entire food groups to
achieve rapid weight loss goals. - D) The study of the economic factors
influencing food production and global supply chains.
Answer B: – Nutrition is defined as the intake of food, considered in relation
to the body's dietary needs. Nutritional science examines the effects of food
components on metabolism, health, performance, and disease resistance.
Rationale: ---
,2. Which term refers to the discipline that applies evidence-based nutritional
science to promote health and treat disease? - A) Nutritional epidemiology -
B) Food science - C) Dietetics - D) Wellness coaching
Answer C: – Dietetics is the discipline that applies nutritional science to
promote health and treat disease.
Rationale: ---
3. Which of the following is an example of an essential nutrient? - A)
Cholesterol - B) Calcium - C) Fiber - D) Phytochemicals
Answer B: – Essential nutrients cannot be synthesized by the body and must
be obtained from food. Calcium is an essential mineral.
Rationale: ---
4. To sustain life, the nutrients in food must perform which three functions?
- A) Provide energy, build tissue, and regulate metabolic processes - B)
Provide energy, store fat, and eliminate waste - C) Build tissue, store
vitamins, and regulate temperature - D) Regulate metabolism, store
minerals, and provide energy
Answer A: – Nutrients provide energy, build and repair tissue, and regulate
metabolic processes.
,Rationale: ---
5. Which macronutrient provides the most energy per gram? - A) Fat (9
kcal/g) - B) Protein (4 kcal/g) - C) Carbohydrate (4 kcal/g) - D) Alcohol (7
kcal/g)
Answer A: – Fat provides 9 kilocalories per gram, more than double the
energy of carbohydrates and proteins.
Rationale: ---
6. What is the primary function of carbohydrates in the body? - A) Build and
repair tissue - B) Provide primary energy source - C) Insulate the body - D)
Regulate body temperature
Answer B: – Carbohydrates are the body's primary and preferred energy
source, providing 4 kcal per gram.
Rationale: ---
7. Which of the following is a complete protein? - A) Lentils - B) Brown rice -
C) Eggs - D) Peanut butter
, Answer C: – Complete proteins contain all nine essential amino acids in
adequate amounts. Animal sources (eggs, meat, poultry, fish, dairy) and soy
are complete proteins.
Rationale: ---
8. Which of the following is an incomplete protein? - A) Beans - B) Chicken -
C) Milk - D) Fish
Answer A: – Most plant proteins are incomplete, lacking one or more
essential amino acids.
Rationale: ---
9. How many calories does protein provide per gram? - A) 9 kcal/g - B) 4
kcal/g - C) 7 kcal/g - D) 3 kcal/g
Answer B: – Protein provides 4 kilocalories per gram.
Rationale: ---
10. Which of the following is a non-essential amino acid? - A) Leucine - B)
Lysine - C) Alanine - D) Threonine
Answer C: – Non-essential amino acids can be synthesized by the body.
Alanine is non-essential; leucine, lysine, and threonine are essential.
Practice Questions 1–200
Section 1: Nutrition Science Foundations (Questions 1–20)
1. Which of the following best describes the primary objective of nutritional
science as defined for the WGU D440 course? - A) The study of food
processing techniques and packaging methods for commercial distribution. -
B) The intake of food, considered in relation to the body's dietary needs and
its effects on health. - C) The practice of eliminating entire food groups to
achieve rapid weight loss goals. - D) The study of the economic factors
influencing food production and global supply chains.
Answer B: – Nutrition is defined as the intake of food, considered in relation
to the body's dietary needs. Nutritional science examines the effects of food
components on metabolism, health, performance, and disease resistance.
Rationale: ---
,2. Which term refers to the discipline that applies evidence-based nutritional
science to promote health and treat disease? - A) Nutritional epidemiology -
B) Food science - C) Dietetics - D) Wellness coaching
Answer C: – Dietetics is the discipline that applies nutritional science to
promote health and treat disease.
Rationale: ---
3. Which of the following is an example of an essential nutrient? - A)
Cholesterol - B) Calcium - C) Fiber - D) Phytochemicals
Answer B: – Essential nutrients cannot be synthesized by the body and must
be obtained from food. Calcium is an essential mineral.
Rationale: ---
4. To sustain life, the nutrients in food must perform which three functions?
- A) Provide energy, build tissue, and regulate metabolic processes - B)
Provide energy, store fat, and eliminate waste - C) Build tissue, store
vitamins, and regulate temperature - D) Regulate metabolism, store
minerals, and provide energy
Answer A: – Nutrients provide energy, build and repair tissue, and regulate
metabolic processes.
,Rationale: ---
5. Which macronutrient provides the most energy per gram? - A) Fat (9
kcal/g) - B) Protein (4 kcal/g) - C) Carbohydrate (4 kcal/g) - D) Alcohol (7
kcal/g)
Answer A: – Fat provides 9 kilocalories per gram, more than double the
energy of carbohydrates and proteins.
Rationale: ---
6. What is the primary function of carbohydrates in the body? - A) Build and
repair tissue - B) Provide primary energy source - C) Insulate the body - D)
Regulate body temperature
Answer B: – Carbohydrates are the body's primary and preferred energy
source, providing 4 kcal per gram.
Rationale: ---
7. Which of the following is a complete protein? - A) Lentils - B) Brown rice -
C) Eggs - D) Peanut butter
, Answer C: – Complete proteins contain all nine essential amino acids in
adequate amounts. Animal sources (eggs, meat, poultry, fish, dairy) and soy
are complete proteins.
Rationale: ---
8. Which of the following is an incomplete protein? - A) Beans - B) Chicken -
C) Milk - D) Fish
Answer A: – Most plant proteins are incomplete, lacking one or more
essential amino acids.
Rationale: ---
9. How many calories does protein provide per gram? - A) 9 kcal/g - B) 4
kcal/g - C) 7 kcal/g - D) 3 kcal/g
Answer B: – Protein provides 4 kilocalories per gram.
Rationale: ---
10. Which of the following is a non-essential amino acid? - A) Leucine - B)
Lysine - C) Alanine - D) Threonine
Answer C: – Non-essential amino acids can be synthesized by the body.
Alanine is non-essential; leucine, lysine, and threonine are essential.
