Changes

: When the [[leaf]] becomes [[dehydrated]] the [[Guard Cell|guard cells]] become [[flaccid]] causing the [[stomata]] to close. This prevents [[Carbon Dioxide]] from entering the [[leaf]]. This reduces the rate of [[photosynthesis]] so less [[water]] is used.

: When the [[leaf]] has enough [[water]] the [[Guard Cell|guard cells]] become [[turgid]] causing the [[stomata]] to open. This allows [[Carbon Dioxide]] into [[leaf]]. This increases the rate of [[photosynthesis]] so more [[water]] is used.