CNC Fundamentals of Nutrition Science 2 — Questions and Answers
Question 1: Which enzyme in the small intestine is primarily responsible for breaking down sucrose into glucose and fructose?
- Lactase
- Maltase
- Sucrase (Correct answer)
- Amylase
Correct answer: Sucrase
Sucrase, a brush-border enzyme of the small intestine, cleaves sucrose into its monosaccharide components glucose and fructose.
Question 2: A client consumes 2,500 kcal/day with 300g carbohydrates, 80g fat, and 150g protein. What percentage of calories comes from protein?
- 18%
- 22%
- 24% (Correct answer)
- 26%
Correct answer: 24%
150g protein × 4 kcal/g = 600 kcal; 600 ÷ 2,500 = 24% of total calories.
Question 3: Which lipoprotein is responsible for transporting dietary fats from the intestinal mucosa to peripheral tissues via the lymphatic system?
- VLDL
- LDL
- HDL
- Chylomicron (Correct answer)
Correct answer: Chylomicron
Chylomicrons are assembled in intestinal epithelial cells and enter the lymphatic system (lacteals) to transport dietary triglycerides to peripheral tissues.
Question 4: The Estimated Average Requirement (EAR) is defined as the nutrient intake that meets the needs of what percentage of healthy individuals?
- 25%
- 50% (Correct answer)
- 75%
- 97.5%
Correct answer: 50%
The EAR is the median requirement estimated to meet the needs of 50% of healthy individuals in a specific life stage and gender group.
Question 5: Which fatty acid classification describes a fat with one double bond in its carbon chain?
- Saturated
- Monounsaturated (Correct answer)
- Polyunsaturated
- Trans
Correct answer: Monounsaturated
Monounsaturated fatty acids (MUFAs) contain exactly one carbon–carbon double bond, as seen in oleic acid found in olive oil.
Question 6: In the context of protein quality, which scoring system accounts for both amino acid composition and digestibility to rank protein sources?
- BV (Biological Value)
- PER (Protein Efficiency Ratio)
- PDCAAS (Correct answer)
- NPU (Net Protein Utilization)
Correct answer: PDCAAS
PDCAAS (Protein Digestibility-Corrected Amino Acid Score) is the internationally accepted method that corrects the amino acid score by the protein's true digestibility.
Question 7: Which organ is the primary site for glycogen storage in terms of maintaining blood glucose homeostasis between meals?
- Kidney
- Skeletal muscle
- Liver (Correct answer)
- Adipose tissue
Correct answer: Liver
The liver stores glycogen and releases glucose into the bloodstream during fasting to maintain blood glucose levels, unlike muscle glycogen which is used locally.
CNC Fundamentals of Nutrition Science 2
Which enzyme in the small intestine is primarily responsible for breaking down sucrose into glucose and fructose?