Conversion of `NO_(3) to NO_(2) to NH_(4)` is called ___________ and is catalysed by

Options

A. Nitrate assimilation, nitrate and nitrite reductase
B. Nitrification, nitrate and nitrite reductase
C. Ammonification, glutarmate dehydrogenase
D. Denitrification, transaminase

Answer

**Step-by-Step Solution:**

1. **Understanding the Process**: The question asks about the conversion of nitrate (NO₃⁻) to nitrite (NO₂⁻) and then from nitrite to ammonia (NH₄⁺). This process is essential for nitrogen assimilation in plants.

2. **Identifying the Enzymes**:
- The first step involves the conversion of nitrate to nitrite. This reaction is catalyzed by an enzyme known as **nitrate reductase**.
- The second step involves the conversion of nitrite to ammonia. This reaction is catalyzed by another enzyme known as **nitrite reductase**.

3. **Naming the Process**: The overall process of converting nitrate to nitrite and then to ammonia is referred to as **nitrate assimilation**. This is a crucial biological process that allows plants and animals to incorporate nitrogen into their systems for growth and development.

4. **Final Answer**: Therefore, the conversion of NO₃⁻ to NO₂⁻ to NH₄⁺ is called **nitrate assimilation**, and it is catalyzed by **nitrate reductase** and **nitrite reductase**.

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