Transpiration is

• A. Evaporation of water from the soil
• B. Condensation of water on leaf surfaces
• C. Evaporation of water through stomata in the leaf
• D. Production of water by the plant

Answer: (C)

Transpiration is the loss of water vapor from the plant, primarily through stomata on the leaf surfaces. Water absorbed by the roots travels up the xylem to the leaves, and when stomata are open, water vapor diffuses out to the air. This not only cools the leaf but also creates the pull that moves water and nutrients up the plant. It’s not evaporation from the soil, not condensation on leaves, and not production of water by the plant. The main pathway is water vapor exiting through stomata in the leaves.