Which element is involved in the formation of mitotic spindle?

Options

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

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which element is involved in the formation of the mitotic spindle. The options provided are nitrogen, phosphorus, calcium, and potassium.

2. **Categorizing Nutrients**: Nutrients essential for plants are classified into two categories: macronutrients (needed in large amounts) and micronutrients (needed in small amounts). Calcium is categorized as a micronutrient.

3. **Analyzing Each Element**:
- **Nitrogen**: This is crucial for the formation of proteins, nucleic acids, and other vital compounds in plants but does not directly relate to the formation of the mitotic spindle.
- **Phosphorus**: This element is important for nucleic acids and cell membranes but is not specifically involved in the formation of the mitotic spindle.
- **Calcium**: This element is absorbed in the form of calcium ions and is specifically mentioned as being necessary for the formation of the mitotic spindle during cell division.
- **Potassium**: This element plays a role in various physiological processes, including protein synthesis and the regulation of stomatal opening, but is not directly involved in the formation of the mitotic spindle.

4. **Conclusion**: Based on the analysis, the element that is involved in the formation of the mitotic spindle is **calcium**.

5. **Final Answer**: The correct answer is **calcium**.

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