Why does transpiration happen
It is the evaporation of water from a plan't surface due to gas exchange.
A plant opens the stomata to let in carbon dioxide to produce glucose. This also lets water out due to movement down the water potential gradient when they open.
- Light - The lighter it is, the faster transpiration occurs. This is because stomata open in the light.
- Temperature - The higher the temperature, the faster the transpiration. Warmer water molecules have more energy so they evaporate from the cells inside the leaf faster. This increases the water potential gradient making water diffuse faster.
- Humidity - The lower the humidity, the faster transpiration. The air around the plant is dry therefore lower water potential so increased transpiration.
- Wind - The windier it is, the faster the transpiration rate. Air movement blows water molecules away…