Transpiration is the process by which water vapor is lost from the aerial parts of a plant, mainly through tiny openings called stomata on the leaves.
Why it occurs:
Transpiration happens as a natural consequence of photosynthesis and water movement within the plant.
Here’s how and why it occurs:
- Water movement:
Water absorbed by the roots travels upward through the xylem to reach the leaves. - Evaporation:
Inside the leaf, water evaporates from the surface of mesophyll cells into the air spaces. - Diffusion through stomata:
The water vapor then diffuses out through the stomata into the atmosphere.
Importance of Transpiration:
- Cooling the plant: It helps to cool the leaf surface, much like sweating in humans.
- Water transport: It maintains the upward pull of water (the transpiration pull) from roots to leaves.
- Nutrient distribution: It helps distribute minerals and nutrients dissolved in water throughout the plant.
- Maintaining turgor pressure: It keeps cells firm and supports the structure of the plant.
In summary, transpiration is essential for water movement, nutrient transport, and temperature regulation in plants, even though it leads to some water loss.