Friday, 22 February 2013

2.42 describe the role of stomata in gas exchange

Stomata are minute wholes in the lower epidermis of the leaf. Guard cells regulate the opening and closing of the stomata; allowing carbon dioxide and oxygen to be exchanged between the leaf and the atmosphere. The guard cells absorb water and become turgid- opening the stomata- during the day. At night the guard cells are flaccid and so close the stomata.

9 comments:

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