Leaf fall reduces transpiration loss.

Answer

**Step-by-Step Solution:**

1. **Understanding Transpiration:**
- Transpiration is the process by which water is absorbed by plant roots, moves through the plant, and is released as water vapor from the aerial parts of the plant, primarily the leaves.

2. **Identifying Aerial Parts:**
- Aerial parts of the plant include leaves, stems, and flowers, which are exposed to the air. Roots, being underground, are not part of the aerial parts.

3. **Role of Stomata:**
- Stomata are small openings on the surface of leaves that facilitate gas exchange and water vapor release. When light hits the plant, stomata open, allowing water to evaporate from the leaf surface.

4. **Water Movement:**
- Water is absorbed by the roots, travels up through the stem, and reaches the leaves. Most of the transpiration occurs through the stomata in the leaves.

5. **Impact of Leaf Fall:**
- When leaves fall off the plant, the surface area for transpiration is reduced. Since the majority of water loss occurs through the leaves, fewer leaves mean less transpiration.

6. **Conclusion:**
- Therefore, when leaves fall, the overall rate of transpiration decreases, leading to reduced water loss from the plant. This confirms that the statement "leaf fall reduces transpiration loss" is correct.

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