Transpiration - GCSE Biology Definition

Transpiration is the process by which plants lose water in the form of water vapour through small openings called stomata, which are mostly found on the underside of leaves. This happens when water absorbed by the plant’s roots is transported up through the xylem vessels in the stem to the leaves, where some of it evaporates into the air. Transpiration is important because it helps to cool the plant, aids in the movement of minerals from the soil, and maintains a continuous flow of water through the plant. It also plays a role in the water cycle by returning water to the atmosphere.