Which one of the following clements in plants is not re-mobilised?

Options

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

Answer

To determine which element in plants is not re-mobilized, we need to analyze the options provided and understand the characteristics of each element in relation to plant physiology.

### Step-by-Step Solution:

1. **Understanding Remobilization**:
- Remobilization refers to the ability of plants to reabsorb nutrients from older tissues and transport them to newer growth areas. This process is crucial for the efficient use of nutrients.

2. **Identifying the Elements**:
- The elements in question are Sulphur, Phosphorus, Potassium, and Calcium. We need to evaluate each of these elements to see if they can be remobilized.

3. **Analyzing Sulphur, Phosphorus, and Potassium**:
- Sulphur, Phosphorus, and Potassium are known to be mobile within the plant. They can be reabsorbed from older tissues and transported to new growth areas. This is because they do not form strong structural components in the plant.

4. **Analyzing Calcium**:
- Calcium, on the other hand, is a structural element. It plays a critical role in forming cell walls and is involved in various structural functions within the plant. Once it is incorporated into the plant structure, it cannot be easily remobilized.

5. **Conclusion**:
- Based on the analysis, Calcium is the element that is not remobilized in plants. Therefore, the answer to the question is Calcium.

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