The calorific values of fats, carbohydrates and proteins vary in the order

Options

A. `Fats gt Carbohydrates gt `Proteins
B. `Fatsgt`proteins `gtcarbohydrates`
C. `Carbohydratesgt`proteins` gtFats`
D. Proteins `gtCarbohydrates gtfats`

Answer

To determine the order of calorific values of fats, carbohydrates, and proteins, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Calorific Value**:
- Calorific value refers to the amount of energy released when a substance is completely burned in the presence of oxygen. It is typically measured in kilocalories (kcal) or kilojoules (kJ) per gram.

2. **Calorific Value of Fats**:
- Fats are known to have the highest calorific value among the three biomolecules. On average, fats provide approximately 9 kcal/g of energy when combusted.

3. **Calorific Value of Carbohydrates**:
- Carbohydrates generally have a lower calorific value than fats. They provide about 4 kcal/g of energy upon complete combustion.

4. **Calorific Value of Proteins**:
- Proteins also yield about 4 kcal/g when burned, similar to carbohydrates. However, the exact calorific value can vary slightly depending on the specific protein source.

5. **Comparing the Values**:
- Based on the calorific values:
- Fats: ~9 kcal/g
- Carbohydrates: ~4 kcal/g
- Proteins: ~4 kcal/g

6. **Conclusion**:
- Therefore, the calorific values of fats, carbohydrates, and proteins vary in the order of:
- **Fats > Carbohydrates = Proteins**

### Final Answer:
The calorific values vary in the order: **Fats > Carbohydrates = Proteins**.

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