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

Options

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

Answer

To determine which element in plants is not remobilized, we need to understand the concepts of mobilized and immobilized elements in plants.

### Step-by-Step Solution:

1. **Understanding Mobilization in Plants**:
- In plants, elements can be classified based on their ability to move from older parts of the plant to younger parts. This movement is crucial for the plant's nutrition and growth.

2. **Identifying Mobilized Elements**:
- Mobilized elements are those that can be transported within the plant. They are not localized and can move to where they are needed. Common examples include phosphorus, potassium, and sulfur.

3. **Identifying Immobilized Elements**:
- Immobilized elements, on the other hand, cannot be transported from one part of the plant to another. They are typically part of the structural components of the plant and remain fixed in one form. Calcium is a prime example of an immobilized element.

4. **Analyzing the Options**:
- The options provided are:
- A) Phosphorus
- B) Calcium
- C) Potassium
- D) Sulfur
- We need to identify which of these elements is immobilized.

5. **Evaluating Each Option**:
- **Phosphorus**: This is a mobilized element; it can move within the plant.
- **Calcium**: This is an immobilized element; it is part of the structural components of the plant and cannot be remobilized.
- **Potassium**: This is also a mobilized element; it can be transported within the plant.
- **Sulfur**: This is another mobilized element; it can move within the plant.

6. **Conclusion**:
- The element that is not remobilized in plants is **Calcium** (Option B). It is fixed in one form and is part of the structural components of the plant.

### Final Answer:
**Calcium (Option B)** is the element in plants that is not remobilized.

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