Which one of the following elements in plants is not remobilised ?

Options

A. Calcium
B. Potassium
C. Sulphur
D. Phosphorus

Answer

To determine which element in plants is not remobilized, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Remobilization**:
- Remobilization refers to the ability of plants to relocate nutrients from older tissues to younger tissues. This is particularly important for mobile nutrients.

2. **Identify the Elements in the Question**:
- The elements listed in the question are calcium, potassium, sulphur, and phosphorus.

3. **Classify the Elements Based on Mobility**:
- **Calcium**: It is known to be a non-mobile element. It plays a crucial role in the structural integrity of plant cells, particularly in the formation of the middle lamella, which connects adjacent cells.
- **Potassium**: This is a mobile element that can be remobilized from older leaves to younger ones.
- **Sulphur**: This is also a mobile element, allowing it to be remobilized as needed.
- **Phosphorus**: Similar to potassium and sulphur, phosphorus is considered a mobile nutrient that can be remobilized.

4. **Conclusion**:
- Among the options provided, calcium is the element that is not remobilized. This is due to its structural role in the plant, making it immobile.

### Final Answer:
**Calcium is the element in plants that is not remobilized.**

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