Photosynthesis - Knowledge

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wavelengths, the other up to 700 nm. The former is known as PSII, the latter is PSI. PSI contains only chlorophyll "a", PSII contains primarily chlorophyll "a" with most of the available chlorophyll "b", among other pigments. These include phycobilins, which are the red and blue pigments of red and blue algae, respectively, and fucoxanthol for brown algae and diatoms. The process is most productive when the absorption of quanta is equal in both PSII and PSI, assuring that input energy from the antenna complex is divided between the PSI and PSII systems, which in turn powers the photochemistry.

430: 4143: 5486: 5311: 13519: 3011:, which jumps from chromophore to chromophore towards the reaction center of the photocomplex, a collection of molecules that traps its energy in a chemical form accessible to the cell's metabolism. The exciton's wave properties enable it to cover a wider area and try out several possible paths simultaneously, allowing it to instantaneously "choose" the most efficient route, where it will have the highest probability of arriving at its destination in the minimum possible time. 45: 13549: 13537: 1218: 13629: 13613: 13597: 13585: 13573: 12220: 4626:(formerly called blue-green algae). The geological record indicates that this transforming event took place early in Earth's history, at least 2450–2320 million years ago (Ma), and, it is speculated, much earlier. Because the Earth's atmosphere contained almost no oxygen during the estimated development of photosynthesis, it is believed that the first photosynthetic cyanobacteria did not generate oxygen. Available evidence from geobiological studies of 1990: 13561: 33: 5395: 5500: 1789: 4994: 997: 4467:, remnants of the original algal nucleus located between the inner and outer membranes of the plastid, is present in the cryptophytes (from a red alga) and chlorarachniophytes (from a green alga). Some dinoflagellates that lost their photosynthetic ability later regained it again through new endosymbiotic events with different algae. While able to perform photosynthesis, many of these eukaryotic groups are 5245: 4940:(now a plastoquinone), and that another was from cytochrome f to a step in the carbohydrate-generating mechanisms. These are linked by plastoquinone, which does require energy to reduce cytochrome f. Further experiments to prove that the oxygen developed during the photosynthesis of green plants came from water were performed by Hill in 1937 and 1939. He showed that isolated 5378:. However, these experiments clearly show that temperature affects the rate of carbon assimilation, so there must be two sets of reactions in the full process of carbon assimilation. These are the light-dependent 'photochemical' temperature-independent stage, and the light-independent, temperature-dependent stage. Second, Blackman's experiments illustrate the concept of 5406:, the enzyme that captures carbon dioxide in the light-independent reactions, has a binding affinity for both carbon dioxide and oxygen. When the concentration of carbon dioxide is high, RuBisCO will fix carbon dioxide. However, if the carbon dioxide concentration is low, RuBisCO will bind oxygen instead of carbon dioxide. This process, called 4699: 5201:·m·s and not be saturated at near full sunlight. This higher rate in maize was almost double of those observed in other species such as wheat and soybean, indicating that large differences in photosynthesis exist among higher plants. At the University of Arizona, detailed gas exchange research on more than 15 species of 5382:. Another limiting factor is the wavelength of light. Cyanobacteria, which reside several meters underwater, cannot receive the correct wavelengths required to cause photoinduced charge separation in conventional photosynthetic pigments. To combat this problem, Cyanobacteria have a light-harvesting complex called 977:

changes its configuration in response to sunlight, acting as a proton pump. This produces a proton gradient more directly, which is then converted to chemical energy. The process does not involve carbon dioxide fixation and does not release oxygen, and seems to have evolved separately from the more

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Because that quantum walking takes place at temperatures far higher than quantum phenomena usually occur, it is only possible over very short distances. Obstacles in the form of destructive interference cause the particle to lose its wave properties for an instant before it regains them once again

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The cyclic reaction is similar to that of the non-cyclic but differs in that it generates only ATP, and no reduced NADP (NADPH) is created. The cyclic reaction takes place only at photosystem I. Once the electron is displaced from the photosystem, the electron is passed down the electron acceptor

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compensation point, high optimum temperature, high stomatal resistances and lower mesophyll resistances for gas diffusion and rates never saturated at full sun light. The research at Arizona was designated a Citation Classic in 1986. These species were later termed C4 plants as the first stable

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contains about 10 to 100 chloroplasts. The chloroplast is enclosed by a membrane. This membrane is composed of a phospholipid inner membrane, a phospholipid outer membrane, and an intermembrane space. Enclosed by the membrane is an aqueous fluid called the stroma. Embedded within the stroma are

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discovered two light reactions by testing plant productivity using different wavelengths of light. With the red alone, the light reactions were suppressed. When blue and red were combined, the output was much more substantial. Thus, there were two photosystems, one absorbing up to 600 nm

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uncovered for the first time that differences in leaf anatomy are crucial factors in differentiating photosynthetic capacities among species. In tropical grasses, including maize, sorghum, sugarcane, Bermuda grass and in the dicot amaranthus, leaf photosynthetic rates were around 38−40 μmol

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stacks of thylakoids (grana), which are the site of photosynthesis. The thylakoids appear as flattened disks. The thylakoid itself is enclosed by the thylakoid membrane, and within the enclosed volume is a lumen or thylakoid space. Embedded in the thylakoid membrane are integral and

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are phototrophic and can absorb energy from the sun, but do not harvest carbon from the atmosphere and are therefore not photosynthetic. Instead of chlorophyll they use rhodopsins, which convert light-energy to ion gradients but cannot mediate electron transfer reactions.

1386: 5421:(3 carbon). Phosphoglycolate cannot be metabolized by the Calvin-Benson cycle and represents carbon lost from the cycle. A high oxygenase activity, therefore, drains the sugars that are required to recycle ribulose 5-bisphosphate and for the continuation of the 2381:. Alarm photosynthesis represents a photosynthetic variant to be added to the well-known C4 and CAM pathways. However, alarm photosynthesis, in contrast to these pathways, operates as a biochemical pump that collects carbon from the organ interior (or from the 8940: 4562:, the only prokaryotes performing oxygenic photosynthesis and the only prokaryotes that contain two types of photosystems (type I (RCI), also known as Fe-S type, and type II (RCII), also known as quinone type). The seven remaining prokaryotes have 464:

is by far the most common type of photosynthesis used by living organisms. Some shade-loving plants (sciophytes) produce such low levels of oxygen during photosynthesis that they use all of it themselves instead of releasing it to the atmosphere.

5214:·m·s, and the leaves have two types of green cells, i.e. outer layer of mesophyll cells surrounding a tightly packed cholorophyllous vascular bundle sheath cells. This type of anatomy was termed Kranz anatomy in the 19th century by the botanist 4454:

in two separate events, by engulfing a cyanobacterium. The plastids in all the other groups have either a red or green algal origin, and are referred to as the "red lineages" and the "green lineages". The only known exception is the ciliate

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discovered that chlorophyll "a" will absorb one light, oxidize cytochrome f, while chlorophyll "a" (and other pigments) will absorb another light but will reduce this same oxidized cytochrome, stating the two light reactions are in series.

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to carbon dioxide. Nutrients used in cellular respiration include carbohydrates, amino acids and fatty acids. These nutrients are oxidized to produce carbon dioxide and water, and to release chemical energy to drive the organism's

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phosphate. Most (five out of six molecules) of the glyceraldehyde 3-phosphate produced are used to regenerate ribulose 1,5-bisphosphate so the process can continue. The triose phosphates not thus "recycled" often condense to form

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was awarded to Melvin Calvin in 1961. In parallel, plant physiologists studied leaf gas exchanges using the new method of infrared gas analysis and a leaf chamber where the net photosynthetic rates ranged from 10 to 13 μmol

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fixation in light has four carbons as malate and aspartate. Other species that lack Kranz anatomy were termed C3 type such as cotton and sunflower, as the first stable carbon compound is the three-carbon PGA. At 1000 ppm

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The salvaging pathway for the products of RuBisCO oxygenase activity is more commonly known as photorespiration, since it is characterized by light-dependent oxygen consumption and the release of carbon dioxide.

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Salvaging glycolate is an energetically expensive process that uses the glycolate pathway, and only 75% of the carbon is returned to the Calvin-Benson cycle as 3-phosphoglycerate. The reactions also produce

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At low irradiance, increasing the temperature has little influence on the rate of carbon assimilation. At constant high irradiance, the rate of carbon assimilation increases as the temperature is increased.

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as electron donors. Purple nonsulfur bacteria used a variety of nonspecific organic molecules. The use of these molecules is consistent with the geological evidence that Earth's early atmosphere was highly

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outside the cell by another carbonic anhydrase and are actively pumped into the cell by a membrane protein. They cannot cross the membrane as they are charged, and within the cytosol they turn back into

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These pigments are embedded in plants and algae in complexes called antenna proteins. In such proteins, the pigments are arranged to work together. Such a combination of proteins is also called a

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after it is freed from its locked position through a classic "hop". The movement of the electron towards the photo center is therefore covered in a series of conventional hops and quantum walks.

6529: 5884: 5833: 8311: 1093:. The green part of the light spectrum is not absorbed but is reflected which is the reason that most plants have a green color. Besides chlorophyll, plants also use pigments such as 1063:. These structures can fill most of the interior of a cell, giving the membrane a very large surface area and therefore increasing the amount of light that the bacteria can absorb. 9783:[On the relationship between the phosphate metabolism and photosynthesis I. Variations in phosphate levels in Chlorella pyrenoidosa as a consequence of light-dark changes] 1357:

to use the blue end of the spectrum to grow in the deeper waters that filter out the longer wavelengths (red light) used by above-ground green plants. The non-absorbed part of the

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Badger MR, Andrews JT, Whitney SM, Ludwig M, Yellowlees DC, Leggat W, Price GD (1998). "The diversity and coevolution of Rubisco, plastids, pyrenoids, and chloroplast-based CO

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food directly from carbon dioxide and water using energy from light. However, not all organisms use carbon dioxide as a source of carbon atoms to carry out photosynthesis;

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The process of photosynthesis provides the main input of free energy into the biosphere, and is one of four main ways in which radiation is important for plant life.

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Hildner R, Brinks D, Nieder JB, Cogdell RJ, van Hulst NF (June 2013). "Quantum coherent energy transfer over varying pathways in single light-harvesting complexes".

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At constant temperature, the rate of carbon assimilation varies with irradiance, increasing as the irradiance increases, but reaching a plateau at higher irradiance.

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Genty B, Briantais J, Baker NR (1989). "The relationship between the quantum yield of photosynthetic electron transport and quenching of chlorophyll fluorescence".

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indicates that life existed 3500 Ma, but the question of when oxygenic photosynthesis evolved is still unanswered. A clear paleontological window on cyanobacterial

12055: 263:(ATP), the "energy currency" of cells. Such archaeal photosynthesis might have been the earliest form of photosynthesis that evolved on Earth, as far back as the 5218:

while studying leaf anatomy of sugarcane. Plant species with the greatest photosynthetic rates and Kranz anatomy showed no apparent photorespiration, very low CO

9781:"Über die Beziehungen zwischen Phosphathaushalt und Photosynthese. I. Phosphatspiegelschwankungen bei Chlorella pyrenoidosa als Folge des Licht-Dunkel-Wechsels" 1660:

and contains the four oxidizing equivalents that are used to drive the water-oxidizing reaction (Kok's S-state diagrams). The hydrogen ions are released in the

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area a plant has to capture light (shading by other plants is a major limitation of photosynthesis), the rate at which carbon dioxide can be supplied to the

5169:, Andrew Benson, James Bassham and a score of students and researchers utilizing the carbon-14 isotope and paper chromatography techniques. The pathway of CO 5082: 4695:

Although some of the steps in photosynthesis are still not completely understood, the overall photosynthetic equation has been known since the 19th century.

9906: 7808:"Temperature response of mesophyll conductance. Implications for the determination of Rubisco enzyme kinetics and for limitations to photosynthesis in vivo" 1051:. In its simplest form, this involves the membrane surrounding the cell itself. However, the membrane may be tightly folded into cylindrical sheets called 10950: 7424: 9839:, Whatley FR, Allen MB (1954). "Photosynthesis by isolated chloroplasts. II. Photophosphorylation, the conversion of light into phosphate bond energy". 6559: 5177:

in a fraction of a second in light resulted in a three carbon molecule called phosphoglyceric acid (PGA). For that original and ground-breaking work, a

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As carbon dioxide concentrations rise, the rate at which sugars are made by the light-independent reactions increases until limited by other factors.

5186:·m·s, with the conclusion that all terrestrial plants have the same photosynthetic capacities, that are light saturated at less than 50% of sunlight. 518:

Photosynthesis and cellular respiration are distinct processes, as they take place through different sequences of chemical reactions and in different

9759: 1169:, can contain between 450,000 and 800,000 chloroplasts for every square millimeter of leaf. The surface of the leaf is coated with a water-resistant 506:: while photosynthesis is a process of reduction of carbon dioxide to carbohydrates, cellular respiration is the oxidation of carbohydrates or other 10273: 7927:"Temperature response of nesophyll conductance. Implications for the determination of Rubisco enzyme kinetics and for limitations to photosynthesis 7673:

Earl H, Said Ennahli S (2004). "Estimating photosynthetic electron transport via chlorophyll fluorometry without Photosystem II light saturation".

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is water. Two water molecules are oxidized by the energy of four successive charge-separation reactions of photosystem II to yield a molecule of

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Photosynthesis is vital for climate processes, as it captures carbon dioxide from the air and binds it into plants, harvested produce and soil.

14414: 13667: 8025:"Assessment of wavelength-dependent parameters of photosynthetic electron transport with a new type of multi-color PAM chlorophyll fluorometer" 5015:, elucidated the path of carbon assimilation (the photosynthetic carbon reduction cycle) in plants. The carbon reduction cycle is known as the 10921: 8116: 5153:

came into common usage. Later discovery of anoxygenic photosynthetic bacteria and photophosphorylation necessitated redefinition of the term.

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Steger U, Achterberg W, Blok K, Bode H, Frenz W, Gather C, Hanekamp G, Imboden D, Jahnke M, Kost M, Kurz R, Nutzinger HG, Ziesemer T (2005).

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Although all cells in the green parts of a plant have chloroplasts, the majority of those are found in specially adapted structures called

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cells to form the first plant cells. Therefore, chloroplasts may be photosynthetic bacteria that adapted to life inside plant cells. Like

1589:. Elevating another electron will first require re-reduction of the reaction center. The excited electrons lost from the reaction center ( 14558: 8836: 7082: 6225:"An overview of anoxygenic phototrophic bacteria and their applications in environmental biotechnology for sustainable Resource recovery" 5086: 1545: 1266: 1262: 323: 10548: 7562: 7532: 6037: 5736:

Reece, Jane B.; Urry, Lisa A.; Cain, Michael L.; Wasserman, Steven A.; Minorsky, Peter V.; Jackson, Robert B.; Campbel, Neil A. (2011).

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measure of photosynthetic response and mechanisms. While standard gas exchange photosynthesis systems can measure Ci, or substomatal CO

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The efficiency of both light and dark reactions can be measured, but the relationship between the two can be complex. For example, the

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to support photosynthesis, the availability of water, and the availability of suitable temperatures for carrying out photosynthesis.

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as symbiont. In dinoflagellates and euglenids the plastids are surrounded by three membranes, and in the remaining lines by four. A

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freed by the splitting of water is used in the creation of two important molecules that participate in energetic processes: reduced

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Single lines: pathways common to most lifeforms. Double lines: pathways not in humans (occurs in e.g. plants, fungi, prokaryotes).

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Phosphoglycolate is quickly metabolized to glycolate that is toxic to a plant at a high concentration; it inhibits photosynthesis.

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An even closer form of symbiosis may explain the origin of chloroplasts. Chloroplasts have many similarities with photosynthetic

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Total photosynthesis is limited by a range of environmental factors. These include the amount of light available, the amount of

2216:, which involves carbon-concentration by selective breakdown of photorespiratory glycine, is both an evolutionary precursor to C 14638: 14366: 6641: 2893: 5659: 4450:. Archaeplastida and the photosynthetic Paulinella got their plastids, which are surrounded by two membranes, through primary 2948:

Photosynthesis measurement systems are not designed to directly measure the amount of light the leaf absorbs, but analysis of

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The overall equation for the light-dependent reactions under the conditions of non-cyclic electron flow in green plants is:

14643: 9967: 14831: 5598: 2869: 2124:. The physical separation of RuBisCO from the oxygen-generating light reactions reduces photorespiration and increases CO 10927: 5112:

synthesis of complex carbon compounds out of carbonic acid, in the presence of chlorophyll, under the influence of light

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El-Sharkawy, MA, Hesketh JD (1965). "Photosynthesis among species in relation to characteristics of leaf anatomy and CO

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Hesketh JD, Musgrave R (1962). "Photosynthesis under field conditions. IV. Light studies with individual corn leaves".

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species, have their main photosynthetic organs in their stems. The cells in the interior tissues of a leaf, called the

9935: 168:, a process that produces oxygen. Photosynthetic organisms store the chemical energy so produced within intracellular 13920: 12112: 7526: 7377:

Renewable biological systems for alternative sustainable energy production (FAO Agricultural Services Bulletin – 128)

6041: 5019:, but many scientists refer to it as the Calvin-Benson, Benson-Calvin, or even Calvin-Benson-Bassham (or CBB) Cycle. 116: 8627:

Reyes-Prieto A, Weber AP, Bhattacharya D (2007). "The origin and establishment of the plastid in algae and plants".

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such as hydrogen or hydrogen sulfide, rather than water, as sources of electrons. Cyanobacteria appeared later; the

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Karpilov YS (1960). "The distribution of radioactvity in carbon-14 among the products of photosynthesis in maize".

14381: 10968: 7406: 1440:(see diagram at right). The absorption of a photon by the antenna complex loosens an electron by a process called 56:. Dark red and blue-green indicate regions of high photosynthetic activity in the ocean and on land, respectively. 14663: 14376: 14243: 13955: 12583: 11446: 10659: 9896: 6591: 2089: 1552:

to NADPH (which has functions in the light-independent reaction); at that point, the path of that electron ends.

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diffusion in leaves of C3 plants by analysis of combined gas exchange and chlorophyll fluorescence measurements"

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opened about 2000 Ma, revealing an already-diverse biota of cyanobacteria. Cyanobacteria remained the principal

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concentration in the chloroplast becomes possible to estimate with the measurement of mesophyll conductance or g

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Liu R, Cai R, Zhang J, Sun C (February 2020). "Heimdallarchaeota harness light energy through photosynthesis".

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levels, the addition of integrated chlorophyll fluorescence measurements allows a more precise measurement of C

1582: 1441: 337:. In this process, atmospheric carbon dioxide is incorporated into already existing organic compounds, such as 7585:"Water stress induces different levels of photosynthesis and electron transport rate regulation in grapevines" 5386:. This complex is made up of a series of proteins with different pigments which surround the reaction center. 2972:

assimilation rates. With some instruments, even wavelength dependency of the photosynthetic efficiency can be

15239: 15229: 15094: 14693: 14648: 14400: 13653: 11377: 9676: 6773:"Molecular mechanism of SRP-dependent light-harvesting protein transport to the thylakoid membrane in plants" 6464: 14180: 9284:"The evolutionary diversification of cyanobacteria: molecular-phylogenetic and paleontological perspectives" 6868: 341:(RuBP). Using the ATP and NADPH produced by the light-dependent reactions, the resulting compounds are then 14526: 13289: 12285: 12096: 11683: 11198: 4529: 3688: 361: 12429: 12418: 10928:

Metabolism, Cellular Respiration and Photosynthesis – The Virtual Library of Biochemistry and Cell Biology

9756: 9468: 8535:"Horizontal gene transfer of the algal nuclear gene psbO to the photosynthetic sea slug Elysia chlorotica" 5696: 4737:

was using and the mass of the plant as it grew. After noticing that the soil mass changed very little, he

4225:). This allows the mollusks to survive solely by photosynthesis for several months at a time. Some of the 2987:

increases the efficiency of the energy transport of light significantly. In the photosynthetic cell of an

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Rumpho ME, Worful JM, Lee J, Kannan K, Tyler MS, Bhattacharya D, Moustafa A, Manhart JR (November 2008).

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Tooulakou G, Giannopoulos A, Nikolopoulos D, Bresta P, Dotsika E, Orkoula MG, et al. (August 2016).

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There are four main factors influencing photosynthesis and several corollary factors. The four main are:

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A is the electron acceptor. Therefore, in light, the electron acceptor is reduced and oxygen is evolved.

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inside the leaves, thus allowing carbon fixation to 3-phosphoglycerate by RuBisCO. CAM is used by 16,000

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Since water is used as the electron donor in oxygenic photosynthesis, the equation for this process is:

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Gupta RS, Mukhtar T, Singh B (Jun 1999). "Evolutionary relationships among photosynthetic prokaryotes (

9963: 9931: 9225:"Functional type 2 photosynthetic reaction centers found in the rare bacterial phylum Gemmatimonadetes" 7344: 5938: 4926: 4618:

The biochemical capacity to use water as the source for electrons in photosynthesis evolved once, in a

2740: 2585: 2374: 1902: 1862: 1803: 1793: 832:) for water in the electron-supply role; for example some microbes use sunlight to oxidize arsenite to 424: 389: 10429:"Photosynthesis by sugar-cane leaves. A new carboxylation reaction and the pathway of sugar formation" 3392: 15259: 15129: 14741: 14633: 14491: 14476: 14471: 14150: 13862: 13368: 13049: 12611: 12598: 12321: 12062: 6840: 6459:

Kulp TR, Hoeft SE, Asao M, Madigan MT, Hollibaugh JT, Fisher JC, Stolz JF, Culbertson CW, Miller LG,

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proposes that this co-location of genes with their gene products is required for redox regulation of

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also suggest that photosynthesis may have begun about 3.4 billion years ago, though the first direct

3931: 3648: 2634: 2621: 1878: 1226: 1212: 481: 208: 13645: 10980: 10477: 10274:"Citation Classic-Photosynthesis among species in relation to characteristics of leaf anatomy and CO 8112: 7297:"CO2 concentrating mechanisms in cyanobacteria: molecular components, their diversity and evolution" 6639:

Mullineaux CW (1999). "The thylakoid membranes of cyanobacteria: structure, dynamics and function".

4646:(2500–543 Ma), in part because the redox structure of the oceans favored photoautotrophs capable of 4218: 15264: 15254: 15119: 15114: 15084: 14888: 14351: 14233: 13026: 12736: 12523: 12200: 12045: 11095: 5573: 5528: 5232:

in measuring air, both the C3 and C4 plants had similar leaf photosynthetic rates around 60 μmol CO

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molecule of the photosystem II reaction center. That loosened electron is taken up by the primary

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of free energy stored in reduced carbon. (in Part 8: "Global photosynthesis and the atmosphere")

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These two experiments illustrate several important points: First, it is known that, in general,

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Paoli L, Ruscheweyh HJ, Forneris CC, Hubrich F, Kautsar S, Bhushan A, et al. (July 2022).

6844: 6325:"Mitochondria, Chloroplasts in Animal and Plant Cells: Significance of Conformational Matching" 5701: 5568: 5064: 4896: 4860:

showed that the increase in mass of the plant as it grows could not be due only to uptake of CO

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air. He then showed that a plant could restore the air the candle and the mouse had "injured."

4754: 4460: 4341: 4042: 3668: 3336: 3049: 2918: 2794: 2720: 2325:) to photosynthetic cells when stomata are partially or totally closed. This process was named 2121: 2101: 1894: 1489: 1465: 1410: 1282: 948: 283: 260: 252: 11759: 10253: 10219: 10184: 9608:"Bicentenary homage to Dr Jan Ingen-Housz, MD (1730-1799), pioneer of photosynthesis research" 8820: 7044: 5344:

The radiation climate within plant communities is extremely variable, in both time and space.

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In photosynthetic bacteria, the proteins that gather light for photosynthesis are embedded in

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as well as water. However, this was a signaling point to the idea that the bulk of a plant's

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use a simpler method that employs a pigment similar to those used for vision in animals. The

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Verduin J (1953). "A table of photosynthesis rates under optimal, near natural conditions".

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Sánchez-Baracaldo, Patricia; Bianchini, Giorgio; Wilson, Jamie D.; Knoll, Andrew H. (2022).

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Sharma AK, Walsh DA, Bapteste E, Rodriguez-Valera F, Ford Doolittle W, Papke RT (May 2007).

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Demoulin, Catherine F.; Lara, Yannick J.; Lambion, Alexandre; Javaux, Emmanuelle J. (2024).

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Medical Science Monitor: International Medical Journal of Experimental and Clinical Research

480:, the overall process is quite similar in these organisms. There are also many varieties of 15139: 15104: 15099: 15023: 15018: 14973: 14871: 14841: 14836: 14688: 14551: 14541: 14086: 13925: 13714: 13565: 13114: 12390: 12375: 11917: 11814: 11769: 11441: 11000: 10719: 10129: 10043: 9555:

Martin D, Thompson A, Stewart I, Gilbert E, Hope K, Kawai G, Griffiths A (September 2012).

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Gómez-Espinoza O, González-Ramírez D, Bresta P, Karabourniotis G, Bravo LA (October 2020).

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in oceanic gyres, as agents of biological nitrogen fixation, and, in modified form, as the

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was later able to discover the function and significance of the electron transport chain.

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can be measured in a few seconds, allowing the investigation of larger plant populations.

2188:, catalyzed by RuBisCO, produces the three-carbon 3-phosphoglyceric acids directly in the 48:

Composite image showing the global distribution of photosynthesis, including both oceanic

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Astrobiology of Earth: The emergence, evolution and future of life on a planet in turmoil

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Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences

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Verduin J, Whitwer EE, Cowell BC (July 1959). "Maximal photosynthetic rates in nature".

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Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences

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of their plant host cells and the genes in this chloroplast DNA resemble those found in

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In plants, algae, and cyanobacteria, sugars are synthesized by a subsequent sequence of

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This initial incorporation of carbon into organic compounds is known as carbon fixation

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can diffuse out, RuBisCO concentrated within the carboxysome quickly sponges it up. HCO

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A collection of photosynthesis pages for all levels from a renowned expert (Govindjee)

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Gest H (2002). "History of the word photosynthesis and evolution of its definition".

9717: 9690: 9629: 9588: 9521: 9496: 9488: 9449: 9431: 9377: 9349: 9323: 9264: 9209: 9197: 9150: 9099: 9048: 8993: 8981: 8941:"Purple reign: life on Earth might once have been dominated by purple microorganisms" 8933: 8874: 8826: 8801: 8752: 8703: 8644: 8609: 8574: 8515: 8505: 8470: 8421: 8384: 8372: 8292: 8163: 8062: 8005: 8000: 7979: 7960: 7907: 7837: 7775: 7698: 7655: 7650: 7617: 7601: 7584: 7522: 7468: 7320: 7277: 7218: 7169: 7126: 7072: 7023: 6992: 6936: 6848: 6810: 6740: 6711: 6618: 6565: 6492: 6409: 6401: 6362: 6344: 6297: 6262: 6244: 6198: 6143: 6100: 6075: 6071:"Primary production of the biosphere: integrating terrestrial and oceanic components" 6003: 5942: 5911: 5860: 5801: 5751: 5743: 5718: 5026: 4888: 4865: 4762: 4742: 4647: 4639: 4456: 4382: 4208: 2539: 2358: 2209: 1882: 1874: 1637: 1621: 1569: 1525: 1449: 1330: 1290: 1056: 974: 530: 393: 193: 137: 129: 10916: 10853: 10206:

Hesketh JD, Moss DN (1963). "Variation in the response of photosynthesis to light".

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of oxygen in marine shelf waters take modern form. Cyanobacteria remain critical to

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can investigate both light and dark reactions when researchers use the two separate

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and therefore contribute to the transmembrane chemiosmotic potential that leads to

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Plants and Microclimate: a Quantitative Approach to Environmental Plant Physiology

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Muscatine L, Greene RW (1973). "Chloroplasts and algae as symbionts in molluscs".

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ions to accumulate within the cell from where they diffuse into the carboxysomes.

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molecules and returns to photosystem I, from where it was emitted, hence the name

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thought that a complex of reactions consisted of an intermediate to cytochrome b

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reaction center. The source of electrons for photosynthesis in green plants and

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Photosynthesis changes sunlight into chemical energy, splits water to liberate O

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