Ammonia formed in the process of biological nitrogen fixation is subsequently used for the synthesis of …………………………………….

Explanation

**Step-by-Step Solution:**

1. **Understanding Biological Nitrogen Fixation**: The process of biological nitrogen fixation involves the conversion of atmospheric nitrogen (N₂) into ammonia (NH₃) by certain bacteria, such as Rhizobium, which live in the root nodules of leguminous plants.

2. **Formation of Ammonia**: During biological nitrogen fixation, atmospheric nitrogen is reduced and transformed into ammonia. This ammonia is crucial for plant growth as it serves as a source of nitrogen.

3. **Subsequent Use of Ammonia**: The ammonia produced is not directly used by plants. Instead, it undergoes further processes. One of the key processes is nitrification, where ammonia is oxidized to nitrites (NO₂⁻) and then to nitrates (NO₃⁻).

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