According to histogen theory, stem epidermis is derived from

Options

A. Calyptrogen
B. Dermatogen
C. Protoderm
D. Periblem

Answer

**Step-by-Step Solution:**

1. **Understanding Histogen Theory**: Histogen theory, proposed by scientist Hanstein, describes the organization of the meristematic tissues in plants. It identifies three primary layers in the shoot and root tips that contribute to the formation of different plant structures.

2. **Identifying the Layers**: According to the histogen theory, the three distinct layers are:
- **Dermatogen**: This is the outermost layer and is responsible for forming the epidermis of the plant.
- **Periblem**: This is the middle layer, located between the dermatogen and the pleurome, and it contributes to the formation of the cortex.
- **Pleurome**: This is the innermost layer, which forms the central core of the plant and gives rise to the vascular tissues.

3. **Focusing on the Epidermis**: The question specifically asks about the stem epidermis. Since the epidermis is formed from the outermost layer, we need to identify which layer corresponds to the epidermis.

4. **Conclusion**: The epidermis of the stem is derived from the **Dermatogen**, which is the primary meristem responsible for forming the outermost layer of the plant.

**Final Answer**: According to histogen theory, the stem epidermis is derived from the **Dermatogen**.

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