Which of the following is not a part of epidermal tissue system

Options

A. Trichomes
B. Companion cells
C. Guard cells
D. Subsidiary cells

Answer

To determine which of the following is not a part of the epidermal tissue system, we need to understand the components of the epidermal tissue system.

### Step-by-Step Solution:

1. **Identify the Epidermal Tissue System**: The epidermal tissue system is the outermost layer of cells in plants. It serves as a protective barrier against environmental factors.

2. **Components of the Epidermal Tissue System**: The epidermal tissue system consists of several components:
- **Epidermis**: The outer layer of cells.
- **Trichomes**: Hair-like structures that can provide protection and reduce water loss.
- **Cuticle**: A waxy layer that covers the epidermis, preventing water loss.
- **Stomata**: Pores that allow gas exchange, consisting of guard cells and subsidiary cells.

3. **Examine the Options**: The question provides multiple options, and we need to identify which one does not belong to the epidermal tissue system. The options include:
- Trichomes
- Guard cells
- Cuticle
- Companion cells

4. **Analyze Each Option**:
- **Trichomes**: Part of the epidermal tissue system.
- **Guard Cells**: Part of the stomata, which are also part of the epidermal tissue system.
- **Cuticle**: A protective layer on the epidermis, part of the epidermal tissue system.
- **Companion Cells**: These are not part of the epidermal tissue system; they are associated with the vascular tissue, specifically in the phloem, and help in the transport of nutrients.

5. **Conclusion**: The option that is not a part of the epidermal tissue system is **Companion Cells**.

### Final Answer:
**Companion Cells** are not a part of the epidermal tissue system.

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