Transpiration mainly takes place through the stomata in the leaves. As water evaporates through the stomata, a thin film of water over the cells is continuous, it results in pulling of water, molecule by molecule, into the leaf from the xylem. Also, because of lower concentration of water vapour in the atmosphere as compared to the substomatal cavity and intercellular spaces, water diffuses into the surrounding air. This creates a transpiration ‘puli’.
Factors Affecting Transpiration Temperature, light, humidity and wind speed.
Importance of Transpiration Transport of liquids and minerals is facilitated because of transpiration