Plant growth in length is due to acivity of

Options

A. apical meristem
B. dermatogen
C. periblem
D. lateral meristem

Answer

**Step-by-Step Solution:**

1. **Understanding Plant Growth**: Plant growth can occur in two main ways: in length (primary growth) and in thickness (secondary growth). For this question, we are focusing on growth in length.

2. **Identifying the Meristematic Tissues**: The primary growth in plants is primarily due to the activity of meristematic tissues. These tissues are regions of actively dividing cells.

3. **Types of Meristematic Tissues**: There are two main types of meristematic tissues:
- **Apical Meristem**: Located at the tips of roots and shoots.
- **Lateral Meristem**: Responsible for growth in thickness.

4. **Role of Apical Meristem**: The apical meristem is responsible for the elongation of the plant. It is found at the shoot tips and root tips, where it facilitates the primary growth of the plant.

5. **Structure of Apical Meristem**: The apical meristem consists of three distinct layers:
- **Dermatogen**: The outer layer that forms the epidermis.
- **Periblem**: The middle layer that contributes to the cortex.
- **Pleurome**: The inner layer that forms the vascular tissues.

6. **Conclusion**: Therefore, the growth in length of the plant is due to the activity of the **apical meristem**.

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