which one is both osmoregulator as well as nitrogenous products

Options

A. `NH_(3)`
B. Urea
C. Uric acid
D. All the above

Answer

To answer the question "which one is both an osmoregulator as well as a nitrogenous product," we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Terms**:
- **Osmoregulator**: A substance that helps maintain the balance of water and salts in the body.
- **Nitrogenous Product**: Waste products formed from the breakdown of proteins, specifically from amino acids.

2. **Identify Nitrogenous Wastes**:
- The primary nitrogenous wastes produced in the body are:
- Ammonia
- Urea
- Uric Acid

3. **Analyze Each Nitrogenous Waste**:
- **Ammonia**: Highly toxic and requires a lot of water for excretion; it is not an osmoregulator.
- **Urea**: Less toxic than ammonia and is soluble in water. It plays a role in osmoregulation by influencing water reabsorption in the kidneys.
- **Uric Acid**: Less soluble and excreted as a paste; it does not significantly contribute to osmoregulation.

4. **Determine the Correct Answer**:
- Among the three nitrogenous wastes, urea is the only one that acts as both a nitrogenous product and an osmoregulator. It helps in the reabsorption of water in the kidneys, thus regulating osmotic pressure.

5. **Conclusion**:
- Therefore, the correct answer to the question is **Urea**.

### Final Answer:
Urea is both an osmoregulator and a nitrogenous product.

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