Ammonia is converted into urea in

Options

A. Heart
B. Spleen
C. Liver
D. Brain

Answer

### Step-by-Step Solution:

1. **Understanding Ammonia**: Ammonia is a nitrogenous waste product that is highly toxic to living organisms. It needs to be converted into a less toxic form for safe excretion.

2. **Urea as a Less Toxic Compound**: Urea is a less toxic nitrogenous waste product compared to ammonia. It is the primary excretory product in ureotelic animals, which include humans.

3. **Identifying the Conversion Process**: The conversion of ammonia into urea occurs through a biochemical process known as the ornithine cycle (or urea cycle).

4. **Location of the Conversion**: The ornithine cycle primarily takes place in the liver. This organ is responsible for detoxifying ammonia by converting it into urea.

5. **Conclusion**: Therefore, the organ where ammonia is converted into urea is the **liver**.

### Final Answer:
Ammonia is converted into urea in the **liver**.

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