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Crassulacean Acid Metabolism (CAM) is a carbon fixation pathway in some photosynthetic plants. CAM is usually found in plants living under arid conditions, including those found in the desert (for example, cacti or pineapple). It is named after the plant family it was first discovered in, the Crassulaceae. Image File history File links Wiki_letter_w. ... Carbon fixation is a process found in autotrophs, usually driven by photosynthesis, whereby carbon dioxide is converted into organic compounds. ... Leaf. ... Divisions Green algae Chlorophyta Charophyta Land plants (embryophytes) Non-vascular plants (bryophytes) Marchantiophyta - liverworts Anthocerotophyta - hornworts Bryophyta - mosses Vascular plants (tracheophytes) †Rhyniophyta - rhyniophytes †Zosterophyllophyta - zosterophylls Lycopodiophyta - clubmosses †Trimerophytophyta - trimerophytes Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adderstongues Seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta... This article is about the plant family. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... Genera many, see text The Crassulaceae, or orpine family, is a family of dicotyledons. ...

Synopsis

Plants that are adapted to dry climates are called xerophytes. Some of these plants have small, thick leaves with a reduced surface area. They may also have a thickened cuticle to protect themselves from the environment. The stomata may be sunken into pits. Some xerophytes shed their leaves during the driest seasons and others can store water such as cacti, orchids and bromeliads. CAM plants take up CO2 at night and store it in the vacuoles, as malic acid that can be broken down during the day for sugars. A xerophyte describes a plant that has structural (xeromorphic) and physiological adaptations which enable them to survive, or even thrive, in areas with very little free moisture. ... This article explains the meaning of area as a Physical quantity. ... This is not about surgically created bowel openings; see stoma (medicine) In botany, a stoma (also stomate; plural stomata) is a tiny opening or pore, found mostly on the undersurface of a plant leaf, and used for gas exchange. ... This article is about the plant family. ... Orchid re-directs here; for alternate uses see Orchid (disambiguation) Genera Over 800 See List of Orchidaceae genera. ... Genera See text Bromeliads include epiphytes, such as Spanish moss, and ground plants, such as the Pineapple. ...

These plants close their stomata (tiny pores used for gas exchange) during the day in order to conserve water. Normally, they wouldn't be able to carry out photosynthesis during day because during day stomata of the CAM plants is closed to reduce transpiration and hence reduce water loss, since carbon dioxide from the air wouldn't be available. Therefore, their stomata are open during the night, and it is then that they take in carbon dioxide. They store it as malate and other, simple organic compounds. Malate in particular is easily broken down into pyruvate and CO₂, the former being phosphorylated into phosphoenolpyruvate (PEP) and then be recycled to fix more carbon. In the daytime, the malic acid is removed from the vacuoles and cleaved to produce CO₂ so that it can be re-fixed by RuBisCO and made into sugars. Ribulose-1,5-bisphosphate carboxylase/oxygenase, most commonly known by the shorter name RuBisCO, is an enzyme (EC 4. ...

Crassulacean acid metabolism allows plants to close their stomata (tiny pores used for gas exchange) during the day in order to conserve water and carry out photosynthesis with CO₂ that is taken up during the cool, humid night. CAM metabolism allows plants to grow in environments that would otherwise be far too dry for plant growth or subject to severe droughts. When an environment is too dry for even CAM plants to grow, they can stay alive by re-fixing the same carbon over and over without ever opening their stomata. This is not about surgically created bowel openings; see stoma (medicine) In botany, a stoma (also stomate; plural stomata) is a tiny opening or pore, found mostly on the undersurface of a plant leaf, and used for gas exchange. ... A pore, in general, is some form of opening, usually very small. ...

In some ways, CAM resembles C₄ metabolism, except that CAM plants contain no bundle sheaths around their veins, and C₄ metabolism is continuous (as long as there is light), while CAM occurs only at night. C₄ metabolism physically separates CO₂ fixation from the Calvin cycle, while CAM metabolism temporally separates CO₂ fixation from the Calvin cycle. For other meanings of C4, see C4 (disambiguation) C4 carbon fixation is a common metabolic pathway found in land [[plant](C4 plants). ... Bundle-sheath cells are contained in certain C4 plants. ... Overview of the Calvin cycle and carbon fixation The Calvin cycle (or Calvin-Benson cycle or carbon fixation) is a series of biochemical reactions that takes place in the stroma of chloroplasts in photosynthetic organisms. ...

CAM plants are very good at retaining water, and are very efficient with nitrogen. The drawback is that they are slow growing.

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