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(Nueva página: Ehleringer, J. R., Monson, R. K. 1993. Evolutionary and ecological aspects of photosynthetic pathway variation. Annual review of ecology and systematics 24:411-439 ==Abstract== C4{{re...)
 
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#{{notas|CAM}}. ''Crassulacean acid metabolism'', also known as ''CAM photosynthesis'', is a carbon fixation pathway that evolved in some plants as an adaptation to arid conditions. In a plant using full CAM, the stomata in the leaves remain shut during the day to reduce evapotranspiration, but open at night to collect carbon dioxide (CO<sub>2</sub>). The CO<sub>2</sub>) is stored as the four-carbon acid malate in vacuoles at night, and then in the daytime, the malate is transported to chloroplasts where it is converted back to CO<sub>2</sub>), which is then used during photosynthesis. The pre-collected CO<sub>2</sub>) is concentrated around the enzyme RuBisCO, increasing photosynthetic efficiency. This metabolism was first studied in plants of the ''Crassulaceae'' family. These mainly include succulents. The first time it was studied, '''Crassula''' was used as a model organism.
 
#{{notas|CAM}}. ''Crassulacean acid metabolism'', also known as ''CAM photosynthesis'', is a carbon fixation pathway that evolved in some plants as an adaptation to arid conditions. In a plant using full CAM, the stomata in the leaves remain shut during the day to reduce evapotranspiration, but open at night to collect carbon dioxide (CO<sub>2</sub>). The CO<sub>2</sub>) is stored as the four-carbon acid malate in vacuoles at night, and then in the daytime, the malate is transported to chloroplasts where it is converted back to CO<sub>2</sub>), which is then used during photosynthesis. The pre-collected CO<sub>2</sub>) is concentrated around the enzyme RuBisCO, increasing photosynthetic efficiency. This metabolism was first studied in plants of the ''Crassulaceae'' family. These mainly include succulents. The first time it was studied, '''Crassula''' was used as a model organism.
 
#{{notas|C3}}
 
#{{notas|C3}}
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#{{notas|rubisco}}
 
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Revisión del 22:04 28 sep 2016

Ehleringer, J. R., Monson, R. K. 1993. Evolutionary and ecological aspects of photosynthetic pathway variation. Annual review of ecology and systematics 24:411-439

Abstract

C4[1] and [2] photosynthesis are evolutionarily derived from C3[3] photosynthesis. The morphological and biochemical modifications necessary to achieve either C4 or CAM photosynthesis are thought to have independently arisen numerous times within different higher plant taxa. It is thought that C4 photosynthesis evolved in response to the low atmospheric CO2 Concentrations that arose sometime after the end of the Cretaceous. LoW CO2 concentrations result in significant increases in photorespiration of C3 plants, reducing productivity; both C3-C4 intermediate and C4 Plants exhibit reduced photorespiration rates. In contrast, it may be argued that CAM arose either in response to selection of increased water-use efficiency or for increased carbon gain. Globally, all three pathways are widely distributed today, with a tendency toward ecological adaptation Of C4 plants into warm, monsoonal climates and CAM plants into water-limited habitats. In an anthropogenically altered CO2 environment, C4 plants may lose their competitive advantage over C3 plants.

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  2. ^ . Crassulacean acid metabolism, also known as CAM photosynthesis, is a carbon fixation pathway that evolved in some plants as an adaptation to arid conditions. In a plant using full CAM, the stomata in the leaves remain shut during the day to reduce evapotranspiration, but open at night to collect carbon dioxide (CO2). The CO2) is stored as the four-carbon acid malate in vacuoles at night, and then in the daytime, the malate is transported to chloroplasts where it is converted back to CO2), which is then used during photosynthesis. The pre-collected CO2) is concentrated around the enzyme RuBisCO, increasing photosynthetic efficiency. This metabolism was first studied in plants of the Crassulaceae family. These mainly include succulents. The first time it was studied, Crassula was used as a model organism.
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