An Adaptation to Xerophytic Conditions: The CAM Plants
Photosynthesis involves the exchange of carbon dioxide and oxygen which occurs through the stomata of the leaf epidermis. This exchange, however, also means that water is lost from the leaf, which can cause a problem for the plant. Normally, water loss is controlled by the closure of the stomata during water stress. However, for desert plants, opening the stomata during the day-when light is available for photosynthesiscould cause a potentially harmful loss ofwater . In some plants this problem has been overcome by segregating, on a temporal basis, the fixation and reduction of carbon dioxide.
KeywordsPentose Phosphate Crassulacean Acid Metabolism Desert Plant Leaf Epidermis Remove Carbon Dioxide
- Bidwell, R.G.S . (1983) ‘Carbon nutrition of plants: photosynthesis and respiration’, in Plant Physiology: A Treatise (F.C. Steward, ed.), Vol. VII. Energyand Carbon Metabolism (F.C. Steward and R.G.S. Bidwell, eds.), Academic Press, New York, 287–458.Google Scholar
- Gardestrom, P. and Edwards, G.E. (1985) ‘Leaf mitochondria (C3 +C4 + CAM)’, in Encyclopedia of Plant Physiology. New Series, Vol. 18, Higher Plant Cell Respiration (R. Douce and D.A. Day, eds.), Springer Verlag, Berlin, 314–346.Google Scholar
- Osmond, G.B. and Holtum, J.A.M. (1981) ‘Crassulacean acid metabolism; in The Biochemistry of Plants: A Comprehensive Treatise (P.K. Stumpf and E.E. Conn, eds), Vol. 8, Photosynthesis, (M.D. Hatch and N.K. Boardman, eds.), Academic Press, New York, 283–329.Google Scholar
- Ting, I.P. (1985) Crassulacean acid metabolism. Ann. Rev. Pl. Physiol. 36, 595–622.Google Scholar