Why are hairy structures present on young leaves and petiole in a fern ?

Answer

**Step-by-Step Solution:**

1. **Understanding the Structure**: Young leaves and petioles of ferns often have hairy structures, which are known as Ramenta. These are scaly, hair-like structures that cover the young parts of the plant.

2. **Function of Hairy Structures**: The primary functions of these hairy structures include:
- **Protection**: The hairs provide a protective covering for the young leaves and petioles. This helps shield them from herbivores and environmental stressors.
- **Reduction of Transpiration**: The presence of hairs can help reduce water loss through transpiration. By creating a microenvironment around the leaf surface, the hairs can trap moisture and decrease the rate at which water evaporates.

3. **Examples in Ferns**: In certain ferns, such as Diopteris, these hairy structures are particularly prominent and serve the functions mentioned above.

4. **Conclusion**: The hairy structures on young leaves and petioles in ferns serve crucial roles in protection and moisture retention, which are vital for the survival of these young plant parts.

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