TAMU Ansc 303 Final (general) ACTUAL EXAM
QUESTIONS WITH COMPLETE SOLUTION GUIDE (A+
GRADED 100% VERIFIED) LATEST VERSION 2026.
DOMAIN 1: Nutrient Classification & Proximate Analysis (10 Questions)
Question 1 (Multiple-Choice)
Which of the following is classified as a macronutrient required in the largest quantity by all
animals and is often the most overlooked nutrient in ration formulation?
A. Carbohydrates
B. Proteins
C. Lipids
D. Water
[CORRECT: D]
Rationale: Water is the most abundant nutrient in the animal body (comprising 50–80% of body
weight) and is required in the greatest quantity. Animals can survive longer without any other
nutrient than they can without water. Water functions as a universal solvent, transport medium,
temperature regulator, and participant in hydrolysis reactions. Despite its critical importance,
water is frequently the most overlooked nutrient in practical ration formulation.
Question 2 (SATA)
Which of the following are the six major nutrient classes required by animals? (Select all that
apply.)
A. Water
B. Carbohydrates
C. Proteins
D. Lipids
E. Vitamins
F. Minerals
G. Enzymes
,[CORRECT: A, B, C, D, E, F]
Rationale: The six major nutrient classes are water, carbohydrates, proteins, lipids, vitamins,
and minerals. Each class serves distinct physiological functions: water (solvent, transport,
thermoregulation); carbohydrates (energy, structural components); proteins (tissue synthesis,
enzymes, hormones); lipids (energy storage, membrane structure, hormone precursors);
vitamins (organic coenzymes and regulators); and minerals (inorganic structural and catalytic
components). Enzymes (Option G) are proteins synthesized by the body, not a nutrient class.
Question 3 (Multiple-Choice)
In the Weende Proximate Analysis system, crude protein (CP) is determined by measuring total
nitrogen via the Kjeldahl method and multiplying by which factor?
A. 5.70
B. 6.25
C. 7.20
D. 16.00
[CORRECT: B]
Rationale: Crude Protein (CP) is calculated as Nitrogen (N) × 6.25. This conversion factor is
derived from the average nitrogen content of amino acids, which is approximately 16%.
Therefore, 100/16 = 6.25. The Kjeldahl procedure involves digesting the sample in concentrated
sulfuric acid with a catalyst, distilling the liberated ammonia into boric acid, and titrating to
determine total nitrogen. This measures total nitrogen, including non-protein nitrogen (NPN),
which is why the term "crude" protein is used.
Question 4 (Calculation)
A feed sample is analyzed using the Weende system. The laboratory reports the following
composition on an as-fed basis: Moisture 12%, Crude Protein 16%, Ether Extract 4%, Crude Fiber
8%, Ash 6%. What is the Nitrogen-Free Extract (NFE) percentage?
A. 54%
B. 56%
C. 58%
D. 60%
[CORRECT: A]
Rationale:
, Step 1: The Weende proximate analysis components must sum to 100%:
Moisture + Crude Protein + Ether Extract + Crude Fiber + Ash + NFE = 100%
Step 2: Solve for NFE:
NFE = 100% − (12% + 16% + 4% + 8% + 6%)
NFE = 100% − 46% = 54%
NFE represents the soluble carbohydrates (sugars, starches) and is calculated by difference. It is
an estimate, not a direct measurement, and includes some analytical error from the other
fractions.
Question 5 (SATA)
Which components are directly measured in the Weende Proximate Analysis system? (Select all
that apply.)
A. Moisture (dry matter)
B. Crude Protein (via Kjeldahl nitrogen)
C. Ether Extract (crude fat)
D. Crude Fiber
E. Ash (minerals)
F. Nitrogen-Free Extract (NFE)
G. Acid Detergent Fiber (ADF)
[CORRECT: A, B, C, D, E]
Rationale: The Weende system directly measures five fractions: moisture (by oven drying at
105°C), crude protein (Kjeldahl N × 6.25), ether extract (crude fat soluble in diethyl ether),
crude fiber (residue after sequential acid and alkali boiling), and ash (mineral residue after
combustion at 600°C). NFE (Option F) is calculated by difference, not directly measured. ADF
(Option G) is part of the Van Soest detergent fiber system, not the Weende system.
Question 6 (Multiple-Choice)
The Crude Fiber analysis in the Weende system has a significant limitation because it:
A. Overestimates the total fiber content by including soluble fiber
B. Underestimates the true fiber content because much of the lignin and hemicellulose are
solubilized during the acid and alkali treatment
C. Accurately measures all structural carbohydrates including pectins and gums
D. Is unable to distinguish between cellulose and starch
QUESTIONS WITH COMPLETE SOLUTION GUIDE (A+
GRADED 100% VERIFIED) LATEST VERSION 2026.
DOMAIN 1: Nutrient Classification & Proximate Analysis (10 Questions)
Question 1 (Multiple-Choice)
Which of the following is classified as a macronutrient required in the largest quantity by all
animals and is often the most overlooked nutrient in ration formulation?
A. Carbohydrates
B. Proteins
C. Lipids
D. Water
[CORRECT: D]
Rationale: Water is the most abundant nutrient in the animal body (comprising 50–80% of body
weight) and is required in the greatest quantity. Animals can survive longer without any other
nutrient than they can without water. Water functions as a universal solvent, transport medium,
temperature regulator, and participant in hydrolysis reactions. Despite its critical importance,
water is frequently the most overlooked nutrient in practical ration formulation.
Question 2 (SATA)
Which of the following are the six major nutrient classes required by animals? (Select all that
apply.)
A. Water
B. Carbohydrates
C. Proteins
D. Lipids
E. Vitamins
F. Minerals
G. Enzymes
,[CORRECT: A, B, C, D, E, F]
Rationale: The six major nutrient classes are water, carbohydrates, proteins, lipids, vitamins,
and minerals. Each class serves distinct physiological functions: water (solvent, transport,
thermoregulation); carbohydrates (energy, structural components); proteins (tissue synthesis,
enzymes, hormones); lipids (energy storage, membrane structure, hormone precursors);
vitamins (organic coenzymes and regulators); and minerals (inorganic structural and catalytic
components). Enzymes (Option G) are proteins synthesized by the body, not a nutrient class.
Question 3 (Multiple-Choice)
In the Weende Proximate Analysis system, crude protein (CP) is determined by measuring total
nitrogen via the Kjeldahl method and multiplying by which factor?
A. 5.70
B. 6.25
C. 7.20
D. 16.00
[CORRECT: B]
Rationale: Crude Protein (CP) is calculated as Nitrogen (N) × 6.25. This conversion factor is
derived from the average nitrogen content of amino acids, which is approximately 16%.
Therefore, 100/16 = 6.25. The Kjeldahl procedure involves digesting the sample in concentrated
sulfuric acid with a catalyst, distilling the liberated ammonia into boric acid, and titrating to
determine total nitrogen. This measures total nitrogen, including non-protein nitrogen (NPN),
which is why the term "crude" protein is used.
Question 4 (Calculation)
A feed sample is analyzed using the Weende system. The laboratory reports the following
composition on an as-fed basis: Moisture 12%, Crude Protein 16%, Ether Extract 4%, Crude Fiber
8%, Ash 6%. What is the Nitrogen-Free Extract (NFE) percentage?
A. 54%
B. 56%
C. 58%
D. 60%
[CORRECT: A]
Rationale:
, Step 1: The Weende proximate analysis components must sum to 100%:
Moisture + Crude Protein + Ether Extract + Crude Fiber + Ash + NFE = 100%
Step 2: Solve for NFE:
NFE = 100% − (12% + 16% + 4% + 8% + 6%)
NFE = 100% − 46% = 54%
NFE represents the soluble carbohydrates (sugars, starches) and is calculated by difference. It is
an estimate, not a direct measurement, and includes some analytical error from the other
fractions.
Question 5 (SATA)
Which components are directly measured in the Weende Proximate Analysis system? (Select all
that apply.)
A. Moisture (dry matter)
B. Crude Protein (via Kjeldahl nitrogen)
C. Ether Extract (crude fat)
D. Crude Fiber
E. Ash (minerals)
F. Nitrogen-Free Extract (NFE)
G. Acid Detergent Fiber (ADF)
[CORRECT: A, B, C, D, E]
Rationale: The Weende system directly measures five fractions: moisture (by oven drying at
105°C), crude protein (Kjeldahl N × 6.25), ether extract (crude fat soluble in diethyl ether),
crude fiber (residue after sequential acid and alkali boiling), and ash (mineral residue after
combustion at 600°C). NFE (Option F) is calculated by difference, not directly measured. ADF
(Option G) is part of the Van Soest detergent fiber system, not the Weende system.
Question 6 (Multiple-Choice)
The Crude Fiber analysis in the Weende system has a significant limitation because it:
A. Overestimates the total fiber content by including soluble fiber
B. Underestimates the true fiber content because much of the lignin and hemicellulose are
solubilized during the acid and alkali treatment
C. Accurately measures all structural carbohydrates including pectins and gums
D. Is unable to distinguish between cellulose and starch
