Which one yields the highest energy per gram

Options

A. Carbohydrate
B. Protein
C. Fat
D. Amino acids.

Answer

To determine which substance yields the highest energy per gram, we can analyze the caloric values of carbohydrates, proteins, fats, and amino acids.

### Step-by-Step Solution:

1. **Identify the Energy Values**:
- Carbohydrates: When metabolized, carbohydrates yield approximately **4 kilocalories per gram**.
- Proteins: Proteins also yield about **4 kilocalories per gram** when metabolized.
- Fats: Fats yield the highest energy, approximately **9.5 kilocalories per gram** when metabolized.
- Amino Acids: Amino acids are the building blocks of proteins and yield energy similar to proteins, which is also about **4 kilocalories per gram**.

2. **Compare the Energy Values**:
- From the values identified:
- Carbohydrates: 4 kcal/g
- Proteins: 4 kcal/g
- Fats: 9.5 kcal/g
- Amino Acids: 4 kcal/g
- We can see that fats provide significantly more energy per gram compared to carbohydrates, proteins, and amino acids.

3. **Conclusion**:
- Based on the caloric values, **fats yield the highest energy per gram**, making them the correct answer to the question.

### Final Answer:
**Fats yield the highest energy per gram.**

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