ACF Nutrition Principles 4 — Questions and Answers
Question 1: Which vitamin acts as an antioxidant and is critical for collagen synthesis?
- Vitamin B12
- Vitamin C (Correct answer)
- Vitamin E
- Vitamin B6
Correct answer: Vitamin C
Vitamin C (ascorbic acid) donates electrons to neutralize free radicals and is a required cofactor for prolyl and lysyl hydroxylases in collagen synthesis.
Question 2: In the context of protein quality, which scoring method accounts for digestibility corrections?
- Biological Value (BV)
- Protein Efficiency Ratio (PER)
- PDCAAS (Correct answer)
- Net Protein Utilization (NPU)
Correct answer: PDCAAS
The Protein Digestibility Corrected Amino Acid Score (PDCAAS) multiplies the amino acid score by true fecal digestibility to assess protein quality.
Question 3: Which type of dietary fat is formed during partial hydrogenation of vegetable oils and is considered most harmful to cardiovascular health?
- Omega-3 polyunsaturated fat
- Conjugated linoleic acid (CLA)
- Industrially produced trans fat (Correct answer)
- Medium-chain triglycerides (MCT)
Correct answer: Industrially produced trans fat
Industrially produced trans fats raise LDL and lower HDL cholesterol simultaneously, making them uniquely harmful to heart health.
Question 4: What is the recommended daily intake of sodium for the general adult US population according to the Dietary Guidelines for Americans?
- Less than 1,500 mg/day
- Less than 2,300 mg/day (Correct answer)
- Less than 3,000 mg/day
- Less than 4,000 mg/day
Correct answer: Less than 2,300 mg/day
The Dietary Guidelines for Americans recommend limiting sodium to less than 2,300 mg per day, roughly equivalent to 1 teaspoon of table salt.
Question 5: Which hormone signals satiety to the brain by reducing appetite after a meal?
- Ghrelin
- Cortisol
- Leptin and GLP-1 (Correct answer)
- Insulin alone
Correct answer: Leptin and GLP-1
Leptin (from adipose tissue) and GLP-1 (from intestinal L-cells) are key satiety signals that reduce hunger and food intake after eating.
Question 6: Phytates in whole grains and legumes primarily affect the absorption of which nutrients?
- Fat-soluble vitamins A, D, E, K
- B vitamins thiamine and riboflavin
- Minerals such as zinc, iron, and calcium (Correct answer)
- Omega-3 fatty acids
Correct answer: Minerals such as zinc, iron, and calcium
Phytic acid binds divalent minerals like zinc, iron, and calcium, forming insoluble complexes that reduce their bioavailability.
Question 7: What is the main purpose of blanching vegetables before freezing them for long-term storage?
- To kill all pathogenic bacteria
- To inactivate enzymes that cause color and flavor degradation (Correct answer)
- To increase water-soluble vitamin content
- To improve texture by breaking down cell walls
Correct answer: To inactivate enzymes that cause color and flavor degradation
Blanching inactivates oxidative enzymes (peroxidase, lipoxygenase) that would otherwise degrade color, flavor, and texture during frozen storage.
ACF Nutrition Principles 4
Which vitamin acts as an antioxidant and is critical for collagen synthesis?