In man, the urea is mainly produced in

Options

A. liver
B. spleen
C. kidneys
D. gall bladder

Answer

**Step-by-Step Solution:**

1. **Understanding Urea Production**: Urea is the main nitrogenous waste product in humans and is produced as a result of protein metabolism. Proteins are broken down into amino acids, which contain nitrogen.

2. **Amino Acid Metabolism**: When amino acids are metabolized, they release ammonium ions (NH4+), which are highly toxic and water-soluble. The body needs to convert this toxic substance into a less harmful form for excretion.

3. **Conversion to Urea**: The ammonium ions combine with carbon dioxide (CO2) to form urea (CO(NH2)2) through a process known as the urea cycle. Urea is less toxic and less water-soluble compared to ammonium ions, making it a safer waste product for the body.

4. **Site of Urea Production**: The primary site for the production of urea in humans is the liver. The liver plays a crucial role in detoxifying harmful substances and is responsible for the metabolism of various compounds, including the conversion of ammonia to urea.

5. **Conclusion**: Therefore, the answer to the question "In man, the urea is mainly produced in" is the liver.

**Final Answer**: The liver.

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