Correct order of calorific value is

Options

A. Carbohydrates `gt` Fats `gt` Proteins
B. Fats `gt` Carbohydrates `gt` Proteins
C. Proteins `gt` Carbohydrates `gt` Fats
D. Fats `gt` Proteins `gt` Carbohydrates

Answer

To determine the correct order of calorific value among different biomolecules, we need to understand what calorific value means and how it relates to carbohydrates, fats, and proteins.

### Step-by-Step Solution:

1. **Understanding Calorific Value**:
- Calorific value is the amount of energy produced when a substance is completely burned. It is usually measured in kilojoules per gram (kJ/g) or calories per gram (cal/g).

2. **Identifying Biomolecules**:
- The three main types of biomolecules that we will consider are:
- **Carbohydrates**: These are sugars and starches, which provide energy.
- **Proteins**: These are made of amino acids and also provide energy, but their primary function is for growth and repair.
- **Fats (Lipids)**: These are triglycerides and provide the highest energy content among the three biomolecules.

3. **Calorific Values of Biomolecules**:
- The approximate calorific values for these biomolecules are:
- **Carbohydrates**: ~4 kCal/g
- **Proteins**: ~4 kCal/g
- **Fats**: ~9 kCal/g

4. **Comparing Calorific Values**:
- From the values above, we can see that fats have the highest calorific value, followed by carbohydrates and proteins.
- Therefore, the order of calorific value from highest to lowest is:
- **Fats > Carbohydrates = Proteins**

5. **Conclusion**:
- The correct order of calorific value is: **Fats > Carbohydrates = Proteins**.