Which one of the following is called as partial mineral element?

Options

A. P
B. N
C. S
D. K

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which of the given options (Phosphorus, Nitrogen, Sulphur, Potassium) is referred to as a "partial mineral element."

2. **Defining Mineral Elements**: Mineral elements are essential nutrients for plants, and they are categorized into macronutrients (needed in larger quantities) and micronutrients (needed in smaller quantities).

3. **Identifying the Elements**:
- **Phosphorus**: A macronutrient essential for energy transfer and photosynthesis.
- **Nitrogen**: A macronutrient crucial for protein synthesis and is a part of nucleic acids.
- **Sulphur**: A macronutrient important for amino acids and proteins.
- **Potassium**: A macronutrient involved in various physiological processes, including osmoregulation.

4. **Understanding Partial Mineral Element**: A partial mineral element is one that is not directly absorbed from the soil but requires a transformation process to become usable by plants.

5. **Analyzing Nitrogen**: Nitrogen is abundant in the atmosphere as nitrogen gas (N₂) but cannot be directly utilized by plants. It must undergo nitrogen fixation, a process where microorganisms convert nitrogen gas into ammonia (NH₃), which is then further transformed into nitrites (NO₂⁻) and nitrates (NO₃⁻) that plants can absorb.

6. **Conclusion**: Based on the above analysis, Nitrogen is classified as a partial mineral element because it is not directly absorbed from the soil but rather converted into a usable form through biological processes.

**Final Answer**: Nitrogen is called a partial mineral element.

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