Which of the following is not a modification of plant organ for arid region?

Options

A. Phylloclade
B. Sporophylls
C. Phyllode
D. Spine

Answer

To determine which of the following options is not a modification of plant organs for arid regions, let's analyze each option step by step:

1. **Phalloclade**:
- Definition: A phalloclade is a green, photosynthetic, flattened or rounded succulent stem that may or may not have leaves.
- Function: In arid regions, phalloclades serve as the primary photosynthetic organ, especially when leaves are reduced or modified into spines to minimize water loss.
- Conclusion: This is a modification for survival in arid conditions.

2. **Sporophyll**:
- Definition: A sporophyll is a leaf that bears sporangia, which are structures that produce spores.
- Function: Sporophylls are not specifically adaptations for arid environments; they are more commonly found in pteridophytes and are related to reproduction rather than water conservation.
- Conclusion: This is not a modification for arid regions.

3. **Foliage (Fallowed)**:
- Definition: Foliage refers to modified petioles that can function in the absence of leaves.
- Function: These modifications can assist in photosynthesis and are adaptations found in arid plants.
- Conclusion: This is a modification for arid conditions.

4. **Spine**:
- Definition: Spines are hard, sharp structures that can be modifications of leaves, stems, or roots.
- Function: They serve to deter herbivores and reduce water loss, making them suitable for arid environments.
- Conclusion: This is also a modification for arid regions.

**Final Answer**: The option that is not a modification of plant organs for arid regions is **B. Sporophyll**.