Position of protoxylum in the vascular bundle of dorsiventral leaf is :-

Options

A. Adaxial
B. Abaxial
C. Both (1) & (2)
D. Towards dorsal surface

Answer

**Step-by-Step Solution:**

1. **Understanding Protoxylem**:
- Protoxylem is the early form of xylem that develops first during the growth of the plant. It has smaller and narrower vessels compared to metaxylem, which is formed later and has larger vessels.

2. **Identifying Dorsiventral Leaf**:
- A dorsiventral leaf, also known as a dicot leaf, has two distinct surfaces: the upper surface (adaxial) and the lower surface (abaxial). This is different from isobilateral leaves, which are typically monocot leaves.

3. **Structure of Dorsiventral Leaf**:
- In a dorsiventral leaf, the mesophyll is differentiated into two types: palisade mesophyll (located closer to the adaxial surface) and spongy mesophyll (located closer to the abaxial surface).

4. **Position of Vascular Bundles**:
- Vascular bundles, which contain xylem and phloem, are located within the leaf. In a dorsiventral leaf, the protoxylem is positioned in relation to the adaxial and abaxial surfaces.

5. **Determining the Position of Protoxylem**:
- In the vascular bundles of a dorsiventral leaf, the protoxylem is found on the adaxial side (upper surface), while the metaxylem is located on the abaxial side (lower surface).

6. **Conclusion**:
- Therefore, the position of protoxylem in the vascular bundle of a dorsiventral leaf is on the adaxial side.

**Final Answer**: The position of protoxylem in the vascular bundle of a dorsiventral leaf is **Adaxial**.

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