From which part mineral ions are frequently remobilised?

Answer

### Step-by-Step Solution:

1. **Identify the Source of Mineral Ion Remobilization**:
- Mineral ions are frequently remobilized from older parts of the plant.

2. **Specify the Older Parts**:
- The primary older parts from which these ions are remobilized are the leaves.

3. **Destination of Remobilized Ions**:
- The remobilized mineral ions are transported to the younger regions of the plant. These regions include the growing areas such as the lateral and apical meristems.

4. **Purpose of Remobilization**:
- The remobilization of these ions supports the development of new structures such as flowers, fruits, and seeds, as well as storage organs.

5. **Examples of Readily Mobilized Ions**:
- The mineral ions that are most readily mobilized include phosphorus, sulfur, nitrogen, and potassium.

6. **Exceptions**:
- Some elements that form structural components, such as calcium, are not remobilized.

### Final Answer:
Mineral ions are frequently remobilized from the older parts of the plant, such as leaves, to the younger growing regions like the lateral and apical meristems.

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