ninja icon


•  Transpiration is the inevitable consequence of gas exchange in the leaf

•  Plants transport water from the roots to the leaves to replace losses from transpiration

Transpiration is the loss of water vapour from the stems and leaves of plants

  • Light energy converts water in the leaves to vapour, which evaporates from the leaf via stomata 
  • New water is absorbed from the soil by the roots, creating a difference in pressure between the leaves (low) and roots (high)
  • Water will flow, via the xylem, along the pressure gradient to replace the water lost from leaves (transpiration stream)

Stomata are pores on the underside of the leaf which facilitate gas exchange (needed for photosynthesis)

  • As photosynthetic gas exchange requires stomata to be open, transpiration will be affected by the level of photosynthesis
  • Hence, transpiration is an inevitable consequence of gas exchange in the leaf

Transpiration in Plants