Mineral ions in plants are:

Options

A. Never remobilised
B. Frequently remobilised
C. Always remobilised
D. Remobilised in the form of inorganic ions

Answer

**Step-by-Step Solution:**

1. **Understanding Mineral Ions in Plants:**
- Mineral ions are essential nutrients that plants require for their growth and development. They include both macronutrients (like nitrogen, phosphorus, potassium) and micronutrients (like iron, manganese, zinc).

2. **Concept of Remobilization:**
- Remobilization refers to the process where plants relocate stored mineral ions from older tissues (like mature leaves) to support the growth of new tissues (like young leaves and developing fruits).

3. **Purpose of Remobilization:**
- This process is crucial during periods when the uptake of minerals from the soil is insufficient. It helps buffer the plant against nutrient deficiencies by utilizing stored nutrients.

4. **Mechanism of Remobilization:**
- Remobilization occurs primarily through phloem transport, which allows the movement of nutrients from older parts of the plant to areas where they are needed.

5. **Frequency of Remobilization:**
- Not all mineral ions are remobilized. While some macronutrients (like potassium and magnesium) are frequently remobilized, others (like calcium and manganese) are not remobilized at all or only in specific circumstances.

6. **Evaluating the Options:**
- The options provided in the question are:
1. Never remobilized
2. Frequently remobilized
3. Always remobilized
4. Remobilized in the form of inorganic ions
- Based on the understanding of remobilization, the correct answer is that mineral ions are **frequently remobilized**.

7. **Conclusion:**
- Therefore, the correct option is **option 2: frequently remobilized**.

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