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Question
Succulents are known to keep their stomata closed during the day to check transpiration. How do they meet their photosynthetic CO2 requirements?
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Solution
Succulent (water-storing) plants such as cacti and euphorbias fix CO2 into the organic compounds using PEP carboxylase at night when the stomata are open.
\[\ce{PEP + CO2 -> OAA}\]
\[\ce{OAA ->[Conversion] Malic acid}\]
The. organic compound (malic acid) accumulates throughout the night and is decarboxylated during the day to produce CO2.
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