PHOTOSYNTHESIS
PHOTORESPIRATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Malic Acid Molecules
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Four Carbon Molecules
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They don’t they are at risk for Photorespiration.
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Carboxylic Acid
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Detailed explanation-1: -Cacti store the carbon dioxide they take in during the night in their cells in the form a chemical called malic acid. In CAM plants, carbon dioxide is only gathered at night, when the stomata open.
Detailed explanation-2: -Although the biochemistry of CAM plants is similar to that of C4 plants, the two carboxylations are now separated in time rather than in space. Malic acid is synthesized from carbohydrates, via PEP carboxylase, at night, and is stored in the vacuole.
Detailed explanation-3: -The mechanism was first discovered in plants of the family Crassulaceae. During the night, a plant employing CAM has its stomata open, allowing CO2 to enter and be fixed as organic acids that are stored in vacuoles.
Detailed explanation-4: -CO2 is taken up at night-time and stored in the vacuole as malic acid, which is decarboxylated in the light behind closed stomata and CO2 is released for fixation by rubisco in the chloroplast. The closed stomata through the day help CAM plants to maintain water.