The conversion of dangerous nitrogenous wastes into less toxic excretory matter is carried out in man in the:

Options

A. Blood
B. Liver
C. Kidney
D. Skin

Answer

### Step-by-Step Solution:

1. **Identify the Nitrogenous Waste**: The primary nitrogenous waste produced in the human body is ammonia. Ammonia is highly toxic and needs to be converted into a less harmful substance.

2. **Understand the Conversion Process**: The conversion of ammonia into a less toxic substance occurs through a biochemical process known as the Ornithine cycle (or urea cycle). This cycle is essential for detoxifying ammonia.

3. **Locate the Site of Conversion**: The Ornithine cycle takes place in the liver. The liver cells, known as hepatocytes, are responsible for this conversion process.

4. **Final Product**: The end product of this conversion is urea, which is significantly less toxic than ammonia. Urea can be safely excreted from the body.

5. **Conclusion**: Therefore, the conversion of dangerous nitrogenous wastes into less toxic excretory matter occurs in the liver.

### Final Answer:
The conversion of dangerous nitrogenous wastes into less toxic excretory matter is carried out in man in the **liver**.

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