Which one of the following is not a part of steles ?

Options

A. Pith
B. Vascular bundle
C. Endodermis
D. Pericycle

Answer

To determine which option is not a part of steles, we need to understand what steles are and their components.

### Step-by-Step Solution:

1. **Definition of Steles**: Steles are structures found in the central part of plants, primarily composed of different types of tissues. They are important for the transport of water, nutrients, and support.

2. **Components of Steles**: The main components of steles include:
- **Pith**: The central part of the stele, which is often involved in storage.
- **Vascular Bundles**: These include xylem and phloem, which are responsible for the transport of water and nutrients.
- **Pericycle**: A layer of cells that can give rise to lateral roots and is located just inside the endodermis.

3. **Identifying Non-Components**: The question asks for the part that is not included in the steles.
- **Endodermis**: This is a layer of cells that surrounds the vascular bundles and is part of the cortex of roots and stems. It is located outside the stele, not within it.

4. **Conclusion**: Since the endodermis is not part of the stele but rather surrounds it, the correct answer is that **endodermis is not a part of steles**.

### Final Answer:
The part that is not a part of steles is **endodermis**.

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