The larger shade leaves provide a larger area for absorbing light energy for photosynthesis in a place where light levels are low. In contrast, smaller sun leaves will provide less surface area for the loss of water through transpiration. ... Shoots grow more quickly in height where light levels are low.
It is an advantage for plants in the shades to have leaves with a large surface area because the larger shade leaves provide a larger area for absolving light energy for photosynthetic activities in a place where ligh level is low. While smaller light level leaves will provide less surface area for the loss of water through Transpiration.
