Oldest xylem is that primary xylem found

Options

A. in the centre
B. on the outside of phloem
C. in the sap wood
D. on the outside of xylem

Answer

**Step-by-Step Solution:**

1. **Understanding Xylem Structure**: Xylem is one of the two types of vascular tissue in plants, primarily responsible for the transport of water and nutrients. It consists of primary xylem and secondary xylem.

2. **Identifying Primary and Secondary Xylem**: Primary xylem is formed during the initial growth of the plant, while secondary xylem is produced during secondary growth, which occurs later in the plant's life.

3. **Position of Xylem in Vascular Bundles**: In a typical vascular bundle, xylem is located towards the center, while phloem is positioned towards the outside. This arrangement is crucial for the efficient transport of water and nutrients.

4. **Understanding Secondary Growth**: During secondary growth, the vascular cambium divides and produces new layers of xylem and phloem. As new layers of secondary xylem are formed, the older xylem is pushed towards the center of the stem.

5. **Conclusion**: Therefore, the oldest xylem, which is the primary xylem, is found in the center of the vascular structure.

6. **Final Answer**: The correct option is **A) in the center**.

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