Stomata close during high intensity light to prevent excessive transpiration but why did they close during low intensity of light? Please explain in easy- understand language because i'm in just 10th standard.Image of my book

  • 1
    $\begingroup$ Think closed state as default state, it is the light which opens the stomata, So in the absence of light stomata go backs default(closed or resting or inactive) state. $\endgroup$
    – JM97
    May 19, 2017 at 6:31
  • $\begingroup$ Do you have a source in support of your assertion that high light intensity causes stomata to close? $\endgroup$
    – Alan Boyd
    May 19, 2017 at 8:23

1 Answer 1


The primary function of open stomata is to promote gas exchange in leaf tissue: atmospheric carbon dioxide is a substrate for photosynthesis. A side effect of opening the stomata is an increase of water loss through transpiration. If light intensity is low then photosynthesis will be depressed: under these conditions it makes sense to close the stomata to conserve water.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.