___________, the ammonia obtained from the dead in plants and animals is converted into other forms of nitrogen.

Options

A. Atmospheric nitrogen fixation
B. Nitrification
C. Denitrification
D. Biological nitrogen fixation

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the process by which ammonia obtained from the decomposition of dead plants and animals is converted into other forms of nitrogen.

2. **Identifying the Process**: The process that converts ammonia (NH3) into other nitrogen compounds is known as nitrification.

3. **Role of Bacteria**: During nitrification, specific bacteria play a crucial role. For instance, bacteria like Nitrosomonas convert ammonia into nitrites (NO2-), and then other bacteria, such as Nitrobacter, convert nitrites into nitrates (NO3-).

4. **Energy Production**: The bacteria involved in this process derive energy from the chemical reactions that occur during the conversion of ammonia to nitrites and nitrites to nitrates.

5. **Conclusion**: Therefore, the correct answer to fill in the blank is "Nitrification".

**Final Answer**: Nitrification, the ammonia obtained from the dead in plants and animals is converted into other forms of nitrogen.

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