In plants, a low concentration of N, S and Mo causes

Options

A. inhibition of cell division
B. delay in flowering
C. death of tissue
D. both A and B

Answer

To solve the question regarding the effects of low concentrations of nitrogen (N), sulfur (S), and molybdenum (Mo) in plants, we can break down the information step by step.

### Step-by-Step Solution:

1. **Understanding the Role of Nitrogen (N)**:
- Nitrogen is a crucial component of chlorophyll, which is essential for photosynthesis. It is also a building block for amino acids, which are necessary for protein synthesis.
- **Hint**: Remember that nitrogen is vital for the formation of chlorophyll and proteins.

2. **Understanding the Role of Sulfur (S)**:
- Sulfur is important for the synthesis of amino acids (like cysteine and methionine), proteins, enzymes, and vitamins. It also plays a role in chlorophyll formation and nitrogen fixation.
- **Hint**: Sulfur contributes to protein synthesis and is involved in chlorophyll production.

3. **Understanding the Role of Molybdenum (Mo)**:
- Molybdenum is essential for the conversion of nitrate to nitrite and ammonia, which are forms of nitrogen that plants can use. It also assists in the conversion of inorganic phosphates to organic phosphates and supports cell division.
- **Hint**: Molybdenum is key for nitrogen metabolism and phosphate reactions.

4. **Identifying Symptoms of Deficiency**:
- With low levels of nitrogen, sulfur, and molybdenum, the following symptoms can be expected:
- **Inhibition of Cell Division**: Both sulfur and molybdenum are involved in cell division processes.
- **Delay in Flowering**: A deficiency in nitrogen can lead to delayed flowering due to reduced chlorophyll production, which affects photosynthesis and energy availability for flowering.
- **Tissue Death (Necrosis)**: While tissue death can occur, it is often associated with diseases rather than direct nutrient deficiencies. However, a lack of essential nutrients can weaken the plant’s overall health, making it more susceptible to diseases that cause necrosis.
- **Hint**: Look for symptoms related to cell division, flowering, and overall plant health.

5. **Conclusion**:
- The low concentration of nitrogen, sulfur, and molybdenum in plants primarily leads to:
- Inhibition of cell division
- Delay in flowering
- Therefore, the correct options indicating the effects of these deficiencies would be both A (Inhibition of cell division) and B (Delay in flowering).

### Final Answer:
The low concentration of nitrogen, sulfur, and molybdenum in plants causes inhibition of cell division and delay in flowering.