2.45 understand that transpiration is the evaporation of water from the surface of a plant

2.45 •transpiration is the evaporation of water from the surface of a plant at the leaves

        •it is a side-effect of the way leaves are adapted for photosynthesis

                  •the water escapes from the leaves through the stomata by diffusion 

     

        •transpiration is caused by the evaporation and diffusion of water

                  •the evaporation creates a slight shortage in the leaf, and so more water is drawn up from the rest of the plant through the xylem vessels to replace it

                             •this means more water is drawn up from the roots, creating a constant transpiration of water through the plant