Deficiency of which mineral causes deficiency of N

Options

A. Mo
B. K
C. Mn
D. S

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks which mineral deficiency leads to a deficiency of nitrogen in plants.

2. **Identifying the Options**: The options provided are:
- Option 1: Molybdenum
- Option 2: Potassium
- Option 3: Manganese
- Option 4: Sulphur

3. **Researching the Role of Each Mineral**:
- **Molybdenum**: It is a microelement essential for activating enzymes involved in nitrogen metabolism.
- **Potassium**: Primarily involved in osmoregulation and enzyme activation but not directly linked to nitrogen metabolism.
- **Manganese**: Involved in photosynthesis and enzyme activation but does not directly affect nitrogen metabolism.
- **Sulphur**: Important for protein synthesis and formation of amino acids but not directly responsible for nitrogen metabolism.

4. **Focusing on Molybdenum**: Molybdenum is crucial for the activation of two key enzymes:
- **Nitrogenase**: This enzyme is essential for nitrogen fixation, a process carried out by certain bacteria that convert atmospheric nitrogen into a form usable by plants.
- **Nitrate Reductase**: This enzyme helps incorporate nitrogen from nitrates into proteins.

5. **Consequences of Molybdenum Deficiency**:
- If molybdenum is deficient, nitrogenase cannot function properly, leading to reduced nitrogen fixation.
- Nitrate reductase will also be inactive, resulting in poor incorporation of nitrate nitrogen into proteins.
- The visible symptoms of these deficiencies include chlorosis, where leaves turn pale and yellowish due to insufficient nitrogen.

6. **Conclusion**: Based on the information gathered, the mineral whose deficiency causes nitrogen deficiency in plants is **Molybdenum**.

### Final Answer:
The deficiency of Molybdenum causes deficiency of Nitrogen in plants.

---