Which of the following biomolecules is common to respiration-mediated breakdown of fats, carbohydrates and proteins

Options

A. Pyruvic acid
B. Acetyl CoA
C. Glucose - 6 -phosphate
D. Fructose 1, 6 - bisphosphate

Answer

To solve the question regarding which biomolecule is common to the respiration-mediated breakdown of fats, carbohydrates, and proteins, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Biomolecules Involved in Respiration**:
- Fats, carbohydrates, and proteins are the three main biomolecules that undergo respiration in living organisms.

2. **Breakdown of Carbohydrates**:
- Carbohydrates are primarily broken down into glucose.
- The process starts with glucose being converted into glucose-6-phosphate, then to fructose-1,6-bisphosphate, and ultimately entering the glycolysis pathway.

3. **Breakdown of Fats**:
- Fats are broken down into fatty acids and glycerol.
- The fatty acids are then converted into acetyl coenzyme A (acetyl CoA) through a process called beta-oxidation.

4. **Breakdown of Proteins**:
- Proteins are broken down into amino acids.
- These amino acids can be converted into various intermediates, including pyruvic acid, which can then be transformed into acetyl CoA.

5. **Common Intermediate**:
- After the breakdown of carbohydrates, fats, and proteins, they all converge into a common intermediate, which is acetyl CoA.
- Acetyl CoA then enters the Krebs cycle (Citric Acid Cycle) for further energy production.

6. **Conclusion**:
- The biomolecule that is common to the respiration-mediated breakdown of fats, carbohydrates, and proteins is acetyl coenzyme A (acetyl CoA).

### Final Answer:
The correct answer is **acetyl coenzyme A**.

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