A permanent secondary tissue is produced by the activity of

Options

A. marginal meristem
B. intercalary meristem
C. apical meristem
D. lateral meristem

Answer

To determine which type of meristem is responsible for the production of permanent secondary tissue, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Meristematic Tissues**:
- Meristematic tissues are composed of undifferentiated cells that have the ability to divide and give rise to various plant organs. They are found in regions of active growth.

2. **Types of Meristematic Tissues**:
- There are two main types of meristematic tissues: primary and secondary.
- Primary meristems are responsible for the initial growth of the plant, while secondary meristems contribute to growth in thickness.

3. **Identify the Types of Meristem in the Options**:
- **Marginal Meristem**: Located at the margins of leaves, responsible for primary growth.
- **Intercalary Meristem**: Found at the base of leaves or internodes, responsible for elongation.
- **Apical Meristem**: Located at the tips of roots and shoots, responsible for primary growth.
- **Lateral Meristem**: Located along the sides of stems and roots, responsible for secondary growth.

4. **Determine the Function of Each Meristem**:
- Marginal, intercalary, and apical meristems are primarily involved in primary growth, which increases the length of the plant.
- Lateral meristems, such as vascular cambium and cork cambium, are responsible for secondary growth, which increases the girth of the plant and produces secondary xylem and phloem.

5. **Conclusion**:
- Since the question asks for the meristem that produces permanent secondary tissues, the correct answer is **lateral meristem**.

### Final Answer:
A permanent secondary tissue is produced by the activity of **lateral meristem**.

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