Periderm is produced by

Options

A. phellogen
B. vascular cambium
C. fascicular cambium
D. cork cells

Answer

**Step-by-Step Solution:**

1. **Understanding Periderm**: Periderm is a protective tissue that replaces the epidermis in plants as they grow. It consists of three layers: phelloderm, phellogen, and phellem (cork).

2. **Identifying the Layers**:
- **Phellem (Cork)**: The outer layer that provides protection.
- **Phellogen (Cork Cambium)**: The middle layer that is responsible for producing phellem and phelloderm.
- **Phelloderm**: The innermost layer, which is a thin layer of living cells.

3. **Role of Phellogen**: Phellogen, also known as cork cambium, is a type of lateral meristem that arises from the de-differentiation of parenchyma cells in the cortex of dicot stems. It is crucial for the formation of periderm.

4. **Evaluating the Options**:
- **Collagen**: This is a protein found in animals, not involved in plant tissue formation.
- **Vascular Cambium**: This produces secondary xylem and phloem, not periderm.
- **Vesicular Cambium**: This term is not commonly used in plant anatomy.
- **Cork Cells**: These are produced by phellogen but do not produce periderm themselves.

5. **Conclusion**: The correct answer is that periderm is produced by **phellogen (cork cambium)**.

**Final Answer**: Periderm is produced by phellogen (cork cambium).

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