Nitrogen is usually absorbed and utilised by the plants in the form of

Options

A. Nitrate and ammonia respectively
B. Nitrite and ammonia respectively
C. Ammonia and nitrite repectively
D. Nitrite and nitrite respectively

Answer

**Step-by-Step Solution:**

1. **Understanding Nitrogen in Plants**: Begin by recognizing that nitrogen is an essential nutrient for plants, playing a crucial role in various physiological processes.

2. **Forms of Nitrogen in Soil**: Identify the forms in which nitrogen is present in the soil. In aerobic conditions (where oxygen is available), nitrogen primarily exists as nitrate (NO3-) due to a process called nitrification.

3. **Absorption of Nitrogen**: Explain that plants primarily absorb nitrogen in the form of nitrate. This is because nitrate is the most prevalent form of nitrogen in well-aerated soils where nitrification occurs.

4. **Utilization of Nitrogen**: Discuss that while nitrate is the main form absorbed, plants can also utilize nitrogen in the form of ammonia (NH3). However, nitrate is more commonly absorbed and utilized.

5. **Conclusion**: Conclude that the correct answer to the question is that nitrogen is usually absorbed and utilized by plants in the form of nitrate and sometimes in the form of ammonia.

**Final Answer**: Nitrogen is usually absorbed and utilized by plants in the form of **nitrate (NO3-)** and sometimes as **ammonia (NH3)**.

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