Youngest heart wood is present

Options

A. in the centre
B. just outside sapwood
C. just inner sapwood
D. just outside primary xylem

Answer

**Step-by-Step Solution:**

1. **Understanding the Types of Wood**: In a plant stem, there are two main types of wood: hardwood (also known as duramen) and sapwood (also known as alburnum).

2. **Location of Sapwood and Hardwood**: Sapwood is located on the exterior part of the plant stem, while hardwood is found in the interior. The hardwood is formed from secondary xylem, which is produced during the secondary growth of the plant.

3. **Characteristics of Hardwood**: Hardwood is typically darker in color and harder in texture compared to sapwood. It consists mainly of dead cells that provide structural support to the plant.

4. **Understanding the Growth Process**: The xylem formed from the apical meristem is referred to as primary xylem. As the plant grows, secondary xylem is produced, which contributes to the formation of hardwood.

5. **Identifying the Youngest Hardwood**: The youngest hardwood is located just inside the sapwood. This is because as new layers of xylem are formed, the older layers become part of the hardwood, while the newer layers are still classified as sapwood.

6. **Conclusion**: Therefore, the correct answer to the question "Youngest hardwood is present" is **just inner sapwood**.

**Final Answer**: The youngest hardwood is present just inner the sapwood (Option C).

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