Derivatives of the secondary meristem in the steler region are

Options

A. Phellem and phelloderm
B. Album and primary phloem
C. Duramen and Alburnum
D. Primary xylem and secondary phloem

Answer

To answer the question regarding the derivatives of the secondary meristem in the stelar region, we can break down the solution step by step:

### Step-by-Step Solution:

1. **Understanding Secondary Meristem**:
- Secondary meristems are responsible for the secondary growth in plants, which increases the thickness of the plant. They produce secondary tissues that contribute to the plant's structure.

2. **Identifying Derivatives**:
- The derivatives of secondary meristem include secondary phloem and secondary xylem. These tissues are formed as the plant grows and are crucial for the transport of nutrients and water.

3. **Evaluating Options**:
- Let's analyze the given options:
- **Option 1**: Primary phloem - This is incorrect as primary phloem is not a derivative of secondary meristem.
- **Option 2**: Alburnum and duramen - Alburnum refers to the functional part of the secondary xylem (sapwood), while duramen refers to the non-functional part (heartwood). Both are derivatives of secondary meristem.
- **Option 3**: Primary xylem and secondary phloem - This is incorrect as primary xylem is not a derivative of secondary meristem.
- **Option 4**: Secondary phloem and secondary xylem - This is correct as both are derivatives of secondary meristem.

4. **Conclusion**:
- The correct derivatives of the secondary meristem in the stelar region are **secondary phloem** and **secondary xylem** (which includes both alburnum and duramen).

### Final Answer:
The derivatives of the secondary meristem in the stelar region are **secondary phloem** and **secondary xylem** (which includes alburnum and duramen).

---