the energy in sunlight is used by photosynthetic organisms to make
Metabolism


green sulfur bacteria can use sunlight as a source of energy, while switching between carbon fixation and the fermentation of organic compounds. In many organisms the capture of solar energy is similar in principle to oxidative phosphorylation, as it involves the storage of energy as a proton concentration gradient. This proton motive force then drives ATP synthesis. The electrons needed to drive this electron transport chain come from light-gathering proteins called photosynthetic reaction centres or rhodopsins. Reaction centers are classed into two types depending on the type of photosynthetic pigment present,
104264
Agulhas Front Marine Protected Area


organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth, based on the available nutrients and the available sunlight. Either can be a limiting factor. Phytoplankton tend to thrive where there is plenty of light, and they themselves are a major factor in restricting light penetration to greater depths, so the photosynthetic zone tends to
2436255
Pondoland Marine Protected Area


, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth, based on the available nutrients and the available sunlight. Either can be a limiting factor. Phytoplankton tend to thrive where there is plenty of light, and they themselves are a major factor in restricting light penetration to greater depths, so the photosynthetic
4004486
Chloroplast


Chloroplasts are organelles that conduct photosynthesis, where the photosynthetic pigment chlorophyll captures the energy from sunlight, converts it, and stores it in the energy-storage molecules ATP and NADPH while freeing oxygen from water in plant and algal cells. They then use the ATP and NADPH to make organic molecules from carbon dioxide in a process known as the Calvin cycle. Chloroplasts carry out a number of other functions, including fatty acid synthesis, much amino acid synthesis, and the immune response in plants. The number of chloroplasts per cell varies
6481740
Robberg Marine Protected Area


mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth, based on the available nutrients and the available sunlight. Either can be a limiting factor. Phytoplankton tend to thrive where there is plenty of light, and they themselves are a major factor in restricting light penetration to greater depths, so the photosynthetic zone tends to be shallower in areas of high productivity. Zooplankton feed on the phytoplankton, and are
2085333
Dwesa-Cwebe Marine Protected Area


, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth, based on the available nutrients and the available sunlight. Either can be a limiting factor. Phytoplankton tend to thrive where there is plenty of light, and they themselves are a major factor in restricting light penetration to greater depths, so the photosynthetic zone tends to be shallower in areas of high
2237391
Hluleka Marine Protected Area


phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth, based on the available nutrients and the available sunlight. Either can be a limiting factor. Phytoplankton tend to thrive where there is plenty of light, and they themselves are a major factor in restricting light penetration to greater depths, so the photosynthetic zone tends to be shallower in areas of high productivity. Zooplankton feed on the phytoplankton
3153164
Jutten Island Marine Protected Area


, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth, based on the available nutrients and the available sunlight. Either can be a limiting factor. Phytoplankton tend to thrive where there is plenty of light, and they themselves are a major factor in restricting light penetration to greater depths, so the photosynthetic zone tends to be shallower
3251439
Southwest Indian Seamounts Marine Protected Area


food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth, based on the available nutrients and the available sunlight. Either can be a limiting factor. Phytoplankton tend to thrive where there is plenty of light, and they themselves are a major factor in restricting light penetration to greater depths, so the photosynthetic zone tends to be shallower in areas of high productivity. Zooplankton
2902538
Light-dependent reactions


transmembrane proton gradient is used to make ATP via ATP synthase. The overall process of the photosynthetic electron transport chain in chloroplasts is: PS II is extremely complex, a highly organized transmembrane structure that contains a "water-splitting complex", chlorophylls and carotenoid pigments, a "reaction center" (P680), pheophytin (a pigment similar to chlorophyll), and two quinones. It uses the energy of sunlight to transfer electrons from water to a mobile electron carrier in the membrane called "plastoquinone": Plastoquinone, in
3205105
Algae bioreactor


to produce fuels such as biodiesel and bioethanol, to generate animal feed, or to reduce pollutants such as NO and CO in flue gases of power plants. Fundamentally, this kind of bioreactor is based on the photosynthetic reaction which is performed by the chlorophyll-containing algae itself using dissolved carbon dioxide and sunlight energy. The carbon dioxide is dispersed into the reactor fluid to make it accessible for the algae. The bioreactor has to be made out of transparent material. The algae are photoautotroph organisms which perform oxygenic photosynthesis. The equation
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Metabolism


different forms of metabolism depend on redox reactions that involve the transfer of electrons from reduced donor molecules such as organic molecules, water, ammonia, hydrogen sulfide or ferrous ions to acceptor molecules such as oxygen, nitrate or sulfate. In animals, these reactions involve complex organic molecules that are broken down to simpler molecules, such as carbon dioxide and water. In photosynthetic organisms, such as plants and cyanobacteria, these electron-transfer reactions do not release energy but are used as a way of storing energy absorbed from sunlight. The
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Deep sea community


at this depth). The ocean can be conceptualized as being divided into various zones, depending on depth, and presence or absence of sunlight. Nearly all life forms in the ocean depend on the photosynthetic activities of phytoplankton and other marine plants to convert carbon dioxide into organic carbon, which is the basic building block of organic matter. Photosynthesis in turn requires energy from sunlight to drive the chemical reactions that produce organic carbon. The stratum of the water column up till which sunlight penetrates is referred to as the photic zone.
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Photosynthetic efficiency


for the same amount of photosynthesis. For actual sunlight, where only 45% of the light is in the photosynthetically active wavelength range, the theoretical maximum efficiency of solar energy conversion is approximately 11%. In actuality, however, plants do not absorb all incoming sunlight (due to reflection, respiration requirements of photosynthesis and the need for optimal solar radiation levels) and do not convert all harvested energy into biomass, which results in a maximum overall photosynthetic efficiency of 3 to 6% of total solar radiation. If photosynthesis is
12680006
Solar fuel


then is used to form hydrogen. The other major indirect process using sunlight is conversion of biomass to biofuel using photosynthetic organisms; however, most of the energy harvested by photosynthesis is used in life-sustaining processes and therefore lost for energy use. A direct process can use a catalyst that reduces protons to molecular hydrogen upon electrons from an excited photosensitizer. Several such catalysts have been developed as proof of concept, but not yet scaled up for commercial use; nevertheless, their relative simplicity gives the advantage of potential lower cost and
21161602
Table Mountain National Park Marine Protected Area


The open sea The pelagic water column is the major part of the living space at sea. This is the water between the surface and the top of the benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth, based on the available nutrients and the available sunlight. Either can be a limiting
14973600
Browns Bank Corals Marine Protected Area


part of the living space at sea. This is the water between the surface and the top of the benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth, based on the available nutrients and the available sunlight. Either can be a limiting factor. Phytoplankton tend to thrive where there is
2029481
Orange Shelf Edge Marine Protected Area


water above the sand. The open sea The pelagic water column is the major part of the living space at sea. This is the water between the surface and the top of the benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth, based on the available nutrients and the available sunlight
2539936
Amathole Offshore Marine Protected Area


column is the major part of the living space at sea. This is the water between the surface and the top of the benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth, based on the available nutrients and the available sunlight. Either can be a limiting factor. Phytoplankton tend to
2602137
Namaqua Fossil Forest Marine Protected Area


water column is the major part of the living space at sea. This is the water between the surface and the top of the benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth, based on the available nutrients and the available sunlight. Either can be a limiting factor. Phytoplankton tend
2839538
Benguela Bank Marine Protected Area


the sand. The open sea The pelagic water column is the major part of the living space at sea. This is the water between the surface and the top of the benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth, based on the available nutrients and the available sunlight. Either
3006739
Namaqua National Park Marine Protected Area


above the sand. The open sea The pelagic water column is the major part of the living space at sea. This is the water between the surface and the top of the benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth, based on the available nutrients and the available sunlight.
3251576
Langebaan Lagoon Marine Protected Area


of the benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth, based on the available nutrients and the available sunlight. Either can be a limiting factor. Phytoplankton tend to thrive where there is plenty of light, and they themselves are a major factor in restricting light penetration to greater depths
3503273
Abyssal plain


by the subduction process. The ocean can be conceptualized as being divided into various zones, depending on depth, and presence or absence of sunlight. Nearly all life forms in the ocean depend on the photosynthetic activities of phytoplankton and other marine plants to convert carbon dioxide into organic carbon, which is the basic building block of organic matter. Photosynthesis in turn requires energy from sunlight to drive the chemical reactions that produce organic carbon. The stratum of the water column nearest the surface of the ocean (sea level) is referred to
9028808
Oxygen


per se. In nature, singlet oxygen is commonly formed from water during photosynthesis, using the energy of sunlight. It is also produced in the troposphere by the photolysis of ozone by light of short wavelength, and by the immune system as a source of active oxygen. Carotenoids in photosynthetic organisms (and possibly animals) play a major role in absorbing energy from singlet oxygen and converting it to the unexcited ground state before it can cause harm to tissues. The common allotrope of elemental oxygen on Earth is called dioxygen, ,
2473302
Benguela Muds Marine Protected Area


benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth, based on the available nutrients and the available sunlight. Either can be a limiting factor. Phytoplankton tend to thrive where there is plenty of light, and they themselves are a major factor in restricting light penetration to greater depths, so
2838827
Bacterioplankton


donor, and the light harvesting pigments used for energy capture. Cyanobacteria are a large group of photosynthetic bacterioplankton, often growing as cells or in filamentous colonies. These organisms are the dominant group of bacterioplankton using oxygenic photosynthesis in aquatic ecosystems. Cyanobacteria, along with photosynthetic eukaryotes, are responsible for approximately half of the total global primary production making them key players in the food web. They use photosynthesis to generate energy in the form of organic compounds and produce oxygen as a byproduct. Major light harvesting pigments include chlorophylls, phycoerytherin,
9805659
Monotropa uniflora


it is white and does not contain chlorophyll. Instead of generating energy from sunlight, it is parasitic, more specifically a mycoheterotroph. Its hosts are certain fungi that are mycorrhizal with trees, meaning it ultimately gets its energy from photosynthetic trees. Since it is not dependent on sunlight to grow, it can grow in very dark environments as in the understory of dense forest. It is often associated with beech trees. The complex relationship that allows this plant to grow also makes propagation difficult. The plant is sometimes completely waxy white
6525681
Spotted jelly


capable of photosynthesis: zooxanthella. This mutualism is based on a life cycle which permits an exchange of energy between the two species. "Mastigias papua" has two different ways of life through 24 hours. During the day, it stays at the surface of the water, in the photic zone. The photic zone is located between the surface of the sea and approximately 100 meters deep. It corresponds to the zone where photosynthetic organisms can use sunlight as an energy source. The jellyfish swims almost 2 kilometres a day, following
1050997
Oxygen


. Most of the mass of living organisms is oxygen as a component of water, the major constituent of lifeforms. Oxygen is continuously replenished in Earth's atmosphere by photosynthesis, which uses the energy of sunlight to produce oxygen from water and carbon dioxide. Oxygen is too chemically reactive to remain a free element in air without being continuously replenished by the photosynthetic action of living organisms. Another form (allotrope) of oxygen, ozone (), strongly absorbs ultraviolet UVB radiation and the high-altitude ozone layer helps protect the biosphere
2473276
Vine training


photosynthetic plant, grapevines need access to sunlight in order to complete their physiological processes. Through photosynthesis, less than 10% of the full sunlight received by a leaf is converted into energy which makes obstacles such as shading even more detrimental to the plant. Even if the leaves at the top of the canopy are receiving plenty of sunlight, the young buds, grape clusters and leaves below will still experience some negative impact. During the annual growth cycle of the grapevine, excessive shading can reduce the success rate of bud formation,
6109295
Photosynthesis


Some organisms employ even more radical variants of photosynthesis. Some archaea use a simpler method that employs a pigment similar to those used for vision in animals. The bacteriorhodopsin 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 common types of photosynthesis. In photosynthetic bacteria, the proteins that gather light for photosynthesis
4838984
Stilbaai Marine Protected Area


energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth, based on the available nutrients and the available sunlight. Either can be a limiting factor. Phytoplankton tend to thrive where there is plenty of light, and they themselves are a major factor in restricting light penetration to greater depths, so the photosynthetic zone tends to be shallower in areas of high productivity. Zooplankton feed on the phytoplankton, and are in turn eaten by larger animals.
4332107
Artificial photosynthesis


expertise. Some techniques employed in making and investigating catalysts and solar cells include: Advantages of solar fuel production through artificial photosynthesis include: Disadvantages include: A concern usually addressed in catalyst design is efficiency, in particular how much of the incident light can be used in a system in practice. This is comparable with photosynthetic efficiency, where light-to-chemical-energy conversion is measured. Photosynthetic organisms are able to collect about 50% of incident solar radiation, however the theoretical limit of photosynthetic efficiency is 4.6 and 6.0%
2914005
Marcus Island Marine Protected Area


drawn through the tunnel, or by extending body parts adapted to this function into the water above the sand. The open sea The pelagic water column is the major part of the living space at sea. This is the water between the surface and the top of the benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are
13904152
Goukamma Marine Protected Area


the water above the sand. The open sea The pelagic water column is the major part of the living space at sea. This is the water between the surface and the top of the benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth, based on the available nutrients and the available
2236504
Port Elizabeth Corals Marine Protected Area


shelter, or may feed by filtering water drawn through the tunnel, or by extending body parts adapted to this function into the water above the sand. The open sea The pelagic water column is the major part of the living space at sea. This is the water between the surface and the top of the benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly
2435629
Agulhas Muds Marine Protected Area


, or may feed by filtering water drawn through the tunnel, or by extending body parts adapted to this function into the water above the sand. The open sea The pelagic water column is the major part of the living space at sea. This is the water between the surface and the top of the benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or
2436758
Robben Island Marine Protected Area


adapted to this function into the water above the sand. The open sea The pelagic water column is the major part of the living space at sea. This is the water between the surface and the top of the benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth, based on the
2539709
Childs Bank Marine Protected Area


by extending body parts adapted to this function into the water above the sand. The open sea The pelagic water column is the major part of the living space at sea. This is the water between the surface and the top of the benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate seas there are distinct seasonal cycles of phytoplankton growth
2839152
UThukela Banks Marine Protected Area


by filtering water drawn through the tunnel, or by extending body parts adapted to this function into the water above the sand. The open sea The pelagic water column is the major part of the living space at sea. This is the water between the surface and the top of the benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly. In temperate
3007021
Malgas Island Marine Protected Area


species can dig themselves holes in which to shelter, or may feed by filtering water drawn through the tunnel, or by extending body parts adapted to this function into the water above the sand. The open sea The pelagic water column is the major part of the living space at sea. This is the water between the surface and the top of the benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic
3859292
Walker Bay Whale Sanctuary


or may feed by filtering water drawn through the tunnel, or by extending body parts adapted to this function into the water above the sand. The open sea The pelagic water column is the major part of the living space at sea. This is the water between the surface and the top of the benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight into organic material which feeds nearly everything else, directly or indirectly
9228995
Photosynthetic efficiency


inefficient, excess light energy must be dissipated to avoid damaging the photosynthetic apparatus. Energy can be dissipated as heat (non-photochemical quenching), or emitted as chlorophyll fluorescence. Quoted values sunlight-to-biomass efficiency The following is a breakdown of the energetics of the photosynthesis process from "Photosynthesis" by Hall and Rao: Starting with the solar spectrum falling on a leaf,br 47% lost due to photons outside the 400–700 nm active range (chlorophyll utilizes photons between 400 and 700 nm, extracting the energy of
12680007
Photosynthetic reaction centre


A photosynthetic reaction center is a complex of several proteins, pigments and other co-factors that together execute the primary energy conversion reactions of photosynthesis. Molecular excitations, either originating directly from sunlight or transferred as excitation energy via light-harvesting antenna systems, give rise to electron transfer reactions along the path of a series of protein-bound co-factors. These co-factors are light-absorbing molecules (also named chromophores or pigments) such as chlorophyll and phaeophytin, as well as quinones. The energy of the photon
8143102
Acropora pulchra


Asia, Japan, the East China Sea and Australia. It chiefly grows at depths which range from on back reef fringes and flats and in reef lagoons, often growing among the closely related coral species "Acropora aspera". The polyps of "Acropora pulchra" extend their tentacles to catch plankton. However, much of the nutrition the coral receives comes from the symbiotic zooxanthellae found in the tissues. These photosynthetic dinoflagellates produce energy when exposed to sunlight and the coral makes use of this. "Acropora" spp. corals are
5932155
Adenosine diphosphate


to replenishment the potential energy of ATP from ADP. Breaking one of ATP's phosphorus bonds generates approximately 30.5 kilojoules per Mole of ATP (7.3 kcal). ADP can be converted, or powered back to ATP through the process of releasing the chemical energy available in food; in humans, this is constantly performed via aerobic respiration in the mitochondria. Plants use photosynthetic pathways to convert and store energy from sunlight, also conversion of ADP to ATP. Animals use the energy released in the breakdown of glucose and other molecules to convert
6798706
Grow light


photosynthetic organisms are able to use in the process of photosynthesis. The irradiance of PAR can be expressed in units of energy flux (W/m), which is relevant in energy-balance considerations for photosynthetic organisms. However, photosynthesis is a quantum process and the chemical reactions of photosynthesis are more dependent on the "number" of photons than the amount of energy contained in the photons. Therefore, plant biologists often quantify PAR using the number of photons in the 400-700 nm range received by a surface for a
5155517
Marion C. Thurnauer


A major area of her research has been solar photochemical energy conversion in bacterial and oxygenic photosynthesis and model photosynthetic systems. Oxygenic photosynthesis is the main process providing energy to the biosphere of the planet, creating the protective ozone layer and consuming carbon dioxide. Photosynthetic organisms use solar energy, converting it into high-energy biochemical compounds. She has modelled the spin and polarization of electrons in photosynthetic systems and helped to develop time-resolved magnetic resonance techniques for the study of sequential electron transfer in photochemical energy conversion. With researchers such as
9917165
Browns Bank Complex Marine Protected Area


. Other species can dig themselves holes in which to shelter, or may feed by filtering water drawn through the tunnel, or by extending body parts adapted to this function into the water above the sand. The open sea The pelagic water column is the major part of the living space at sea. This is the water between the surface and the top of the benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight
2902470
Sardinia Bay Marine Protected Area


. Other species can dig themselves holes in which to shelter, or may feed by filtering water drawn through the tunnel, or by extending body parts adapted to this function into the water above the sand. The open sea The pelagic water column is the major part of the living space at sea. This is the water between the surface and the top of the benthic zone, where living organisms swim, float or drift, and the food chain starts with phytoplankton, the mostly microscopic photosynthetic organisms that convert the energy of sunlight
9163852
Propanil


Propanil is a widely used contact herbicide. With an estimated use of about 8 million pounds in 2001, it is one of the more widely used herbicides in the United States. Propanil is said to be in use in approximately 400,000 acres of rice production each year. The principal mode of propanil's herbicidal action against weeds is inhibition of their photosynthesis and CO fixation. Plants photosynthesize in two stages. In stage I photosynthetic reactions capture sunlight energy and yield molecules with high energy content. In stage II these molecules react to capture
13448664
History of Earth


of the life that covers the surface of the Earth depends directly or indirectly on photosynthesis. The most common form, oxygenic photosynthesis, turns carbon dioxide, water, and sunlight into food. It captures the energy of sunlight in energy-rich molecules such as ATP, which then provide the energy to make sugars. To supply the electrons in the circuit, hydrogen is stripped from water, leaving oxygen as a waste product. Some organisms, including purple bacteria and green sulfur bacteria, use an anoxygenic form of photosynthesis that uses
3941259
Photosynthetically active radiation


m), which is relevant in energy-balance considerations for photosynthetic organisms. However, photosynthesis is a quantum process and the chemical reactions of photosynthesis are more dependent on the number of photons than the energy contained in the photons. Therefore, plant biologists often quantify PAR using the number of photons in the 400-700 nm range received by a surface for a specified amount of time, or the Photosynthetic Photon Flux Density (PPFD). PPFD is normally measured using mol ms. In relation to plant growth and morphology,
222297
Metabolism


their energy: photoautotrophs and photoheterotrophs obtain energy from light, whereas chemoautotrophs and chemoheterotrophs obtain energy from inorganic oxidation reactions. Photosynthesis is the synthesis of carbohydrates from sunlight and carbon dioxide (CO). In plants, cyanobacteria and algae, oxygenic photosynthesis splits water, with oxygen produced as a waste product. This process uses the ATP and NADPH produced by the photosynthetic reaction centres, as described above, to convert CO into glycerate 3-phosphate, which can then be converted into glucose. This carbon-fixation reaction is carried out by the
104268
Microbial mat


infra-red heat emissions from hydrothermal vents. The development of photosynthetic energy generation enabled the microorganisms first to colonize wider areas around vents and then to use sunlight as an energy source. The role of the hydrothermal vents was now limited to supplying reduced metals into the oceans as a whole rather than being the main supporters of life in specific locations. Heterotrophic scavengers would have accompanied the photosynthesizers in their migration out of the "hydrothermal ghetto". The evolution of purple bacteria, which do not produce or use oxygen but can tolerate
3661173
Sunlight


center of the Sun and changing direction every time it encounters a charged particle would take between 10,000 and 170,000 years to get to the surface. Sunlight is a key factor in photosynthesis, the process used by plants and other autotrophic organisms to convert light energy, normally from the Sun, into chemical energy that can be used to synthesize carbohydrates and to fuel the organisms' activities. Researchers can measure the intensity of sunlight using a sunshine recorder, pyranometer, or pyrheliometer. To calculate the amount of sunlight reaching the ground, both
8286595
Calvin cycle


a series of biochemical redox reactions that take place in the stroma of chloroplast in photosynthetic organisms. The cycle was discovered by Melvin Calvin, James Bassham, and Andrew Benson at the University of California, Berkeley by using the radioactive isotope carbon-14. Photosynthesis occurs in two stages in a cell. In the first stage, light-dependent reactions capture the energy of light and use it to make the energy-storage and transport molecules ATP and NADPH. The Calvin cycle uses the energy from short-lived electronically excited carriers to convert
6698221
Microbial metabolism


Archaeon "Halobacterium" or the bacterium "Roseobacter", among others) can utilize light to produce energy using the enzyme bacteriorhodopsin, a light-driven proton pump. However, there are no known Archaea that carry out photosynthesis. As befits the large diversity of photosynthetic bacteria, there are many different mechanisms by which light is converted into energy for metabolism. All photosynthetic organisms locate their photosynthetic reaction centers within a membrane, which may be invaginations of the cytoplasmic membrane (Proteobacteria), thylakoid membranes (Cyanobacteria), specialized antenna
9167792
Autotroph


), meaning "nourishment" or "food". The first autotrophic organism developed about 2 billion years ago. Autotrophs evolved from heterotrophic bacteria by developing photosynthesis. The earliest photosynthetic bacteria used hydrogen sulphide. Due to the scarcity of hydrogen sulphide, some photosynthetic bacteria evolved to use water in photosynthesis, leading to cyanobacteria. Some organisms rely on organic compounds as a source of carbon, but are able to use light or inorganic compounds as a source of energy. Such organisms are not defined as autotrophic, but rather as heterotrophic
6190122
Prochlorophyta


Prochlorophyta is a group of photosynthetic bacteria, an important component of picoplankton. These oligotrophic organisms are abundant in nutrient poor tropical waters and use a unique photosynthetic pigment, divinyl-chlorophyll, to absorb light and acquire energy. Prochlorophyta lack red and blue phycobilin pigments and have stacked thylakoids, making them distinctly different from Cyanobacteria (or Cyanophyta), but some authors consider them as part of the Cyanobacteria, as the group Prochlorales. This unique group of phytoplankton, with no phycobilin pigments, were initially found in 1975 near the Great
6551413
Chlorophyll a


P680 and P700 are located. Chlorophyll "a" is essential for most photosynthetic organisms to release chemical energy but is not the only pigment that can be used for photosynthesis. All oxygenic photosynthetic organisms use chlorophyll "a", but differ in accessory pigments like chlorophyll "b". Chlorophyll "z" can also be found in very small quantities in the green sulfur bacteria, an anaerobic photoautotroph. These organisms use bacteriochlorophyll and some chlorophyll "a" but do not produce oxygen. Anoxygenic photosynthesis is the term applied to this
9740479
Biogeochemical cycle


sun constantly gives the planet energy in the form of light while it is eventually used and lost in the form of heat throughout the trophic levels of a food web. Carbon is used to make carbohydrates, fats, and proteins, the major sources of food energy. These compounds are oxidized to release carbon dioxide, which can be captured by plants to make organic compounds. The chemical reaction is powered by the light energy of the sun. Sunlight is required to combine carbon with hydrogen and oxygen into an energy source, but
14738667
Zostera novazelandica


will be composed entirely of flowering shoots, and the rhizomes do not live through the winter. Annual seagrass’ grow during the spring and die out by the end of autumn. "Zostera novazalendica" relies on photosynthesis for “food”. The species growth habits are restricted to where it can be provided with sunlight. Photosynthesis is “the process by which green plants and some other organisms use sunlight to synthesize nutrients from carbon dioxide and water.” However, the loss of photosynthetic tissue has been proven to not have any
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Tide pool


to drying out and temperature extremes. Low tide zone organisms include abalone, anemones, brown seaweed, chitons, crabs, green algae, hydroids, isopods, limpets, mussels, and sometimes even small vertebrates such as fish. These creatures can grow to larger sizes because there is more available energy and better water coverage: the water is shallow enough to allow additional sunlight for photosynthetic activity, with almost normal levels of salinity. This area is also relatively protected from large predators because of the wave action and shallow water. Tide
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Alternative energy


day, but wind tends to blow slightly more at night than during the day, so, the price of nighttime wind power is often much less expensive than any alternative. Germany has built a 250 kilowatt synthetic methane plant which they are scaling up to 10 megawatts. Algae fuel is a biofuel which is derived from algae. During photosynthesis, algae and other photosynthetic organisms capture carbon dioxide and sunlight and convert it into oxygen and biomass. This is usually done by placing the algae between two panes of glass. The algae creates
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Phototroph


synthesis from light and are capable of using carbon dioxide as their principal source of carbon. Oxygenic photosynthetic organisms use chlorophyll for light-energy capture and oxidize water, "splitting" it into molecular oxygen. In contrast, anoxygenic photosynthetic bacteria have a substance called bacteriochlorophyll – which absorbs predominantly at non-optical wavelengths – for light-energy capture, live in aquatic environments, and will, using light, oxidize chemical substances such as hydrogen sulfide rather than water. In an ecological context, phototrophs are often the food source for
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Carbon fixation


Carbon fixation or сarbon assimilation is the conversion process of inorganic carbon (carbon dioxide) to organic compounds by living organisms. The most prominent example is photosynthesis, although chemosynthesis is another form of carbon fixation that can take place in the absence of sunlight. Organisms that grow by fixing carbon are called autotrophs. Autotrophs include photoautotrophs, which synthesize organic compounds using the energy of sunlight, and lithoautotrophs, which synthesize organic compounds using the energy of inorganic oxidation. Heterotrophs are organisms that grow using the carbon fixed by autotrophs. The organic
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Marine algae and plants


making their own food by gathering around hydrothermal vents and cold seeps and using chemosynthesis. However most marine primary production comes from organisms which use photosynthesis on the carbon dioxide dissolved in the water. This process uses energy from sunlight to convert water and carbon dioxide into sugars that can be used both as a source of chemical energy and of organic molecules that are used in the structural components of cells. Marine primary producers are important because they underpin almost all marine animal life by generating most of the oxygen and food that provide other organisms
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Aureochromes


Aureochromes are blue light photoreceptors as well as transcription factors found only in stramenopiles so far. It was first discovered in "Vaucheria frigida" in 2007 by Takahashi et.al. Photosynthetic eukaryotes mainly convert sunlight into energy via photosynthesis, but light also is important for movement and development, regulation of biological activities. The effective wavelength for light responses in photosynthetic eukaryotes is mainly in the red light (RL) and blue light (BL) regions (Mohr 1980; Furuya 1993). The red/far-red receptor phytochrome and phytochrome
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Biological photovoltaics


being able to self-assemble and self-repair (i.e. the photosynthetic organism is able to reproduce itself). The ability of the organism to store energy allows for power generation from biological photovoltaic systems in the dark, circumventing the grid supply and demand problems sometimes faced by conventional photovoltaics. Additionally, the use of photosynthetic organisms that fix carbon dioxide means the 'assembly' of the light harvesting material in a biological photovoltaic system could have a negative carbon footprint. Compared to microbial fuel cells, which use heterotrophic microorganisms, biological
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Bruce Rittmann


won the 2011 Environmental Engineering Excellence Award from the American Academy of Environmental Engineers. Rittmann’s photobioreactor team is working towards finding practical ways to utilize photosynthetic microorganisms to capture sunlight energy and convert CO into valuable feedstock for fuels and chemicals. The team focuses on advanced photobioreactor systems that give high productivity of the target product. The product can be part of the biomass itself or chemical synthesized and excreted by the photosynthetic microorganisms. The latter theme is in cooperation with Dr. Willem Vermaas of ASU’s School of Life Sciences. The ultimate goal
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Photosynthetic efficiency


53% (in the 400–700 nm range) → 30% of photons are lost due to incomplete absorption, leavingbr 37% (absorbed photon energy) → 24% is lost due to wavelength-mismatch degradation to 700 nm energy, leavingbr 28.2% (sunlight energy collected by chlorophyll) → 32% efficient conversion of ATP and NADPH to d-glucose, leavingbr 9% (collected as sugar) → 35–40% of sugar is recycled/consumed by the leaf in dark and photo-respiration, leavingbr 5.4% net
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Food chain


In the deep sea, food chains centered on hydrothermal vents and cold seeps exist in the absence of sunlight. Chemosynthetic bacteria and archaea use hydrogen sulfide and methane from hydrothermal vents and cold seeps as an energy source (just as plants use sunlight) to produce carbohydrates; they form the base of the food chain. Consumers are organisms that eat other organisms. All organisms in a food chain, except the first organism, are consumers. In a food chain, there is also reliable energy transfer through each stage. However,
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Microbial oxidation of sulfur


belong to the family "Desulfobulbaceae" of the Deltaproteobacteria and are currently represented by two candidate Genera, ""Candidatus" Electronema" and ""Candidatus" Electrothrix""""." Anaerobic SOB (AnSOB) are mainly neutrophilic/mesophilic photosynthetic autotrophs, which obtain energy from sunlight but use reduced sulfur compounds instead of water as electron donors for photosynthesis. AnSOB include some purple sulfur bacteria (Chromatiaceae) such as "Allochromatium", and green sulfur bacteria (Chlorobiaceae), as well as the purple non-sulfur
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Photosynthetic efficiency


leaf efficiency. Many plants lose much of the remaining energy on growing roots. Most crop plants store ~0.25% to 0.5% of the sunlight in the product (corn kernels, potato starch, etc.). Photosynthesis increases linearly with light intensity at low intensity, but at higher intensity this is no longer the case (see Photosynthesis-irradiance curve). Above about 10,000 lux or ~100 watts/square meter the rate no longer increases. Thus, most plants can only utilize ~10% of full mid-day sunlight
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Earth's energy budget


effect: photosynthetic efficiency turns up to 2% of the sunlight striking plants into biomass. 100 to 140 TW (or around 0.08%) of the initial energy gets captured by photosynthesis, giving energy to plants. Other minor sources of energy are usually ignored in these calculations, including accretion of interplanetary dust and solar wind, light from stars other than the Sun and the thermal radiation from space. Earlier, Joseph Fourier had claimed that deep space radiation was significant in a paper often cited as the first on the greenhouse effect
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Carbon fixation


understandable that RuBisCO is the most abundant protein on Earth. Six autotrophic carbon fixation pathways are known as of 2011. The Calvin cycle fixes carbon in the chloroplasts of plants and algae, and in the cyanobacteria. It also fixes carbon in the anoxygenic photosynthetic in one type of proteobacteria called purple bacteria, and in some non-phototrophic proteobacteria. In photosynthesis, energy from sunlight drives the carbon fixation pathway. "Oxygenic" photosynthesis is used by the primary producers—plants, algae, and cyanobacteria. They contain the pigment chlorophyll
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Glucose


Glucose (also called dextrose) is a simple sugar with the molecular formula . Glucose is the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, using energy from sunlight. There it is used to make cellulose in cell walls, which is the most abundant carbohydrate. In energy metabolism, glucose is the most important source of energy in all organisms. Glucose for metabolism is partially stored as a polymer, in plants mainly as starch and amylopectin
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Photosynthetically active radiation


Photosynthetically active radiation, often abbreviated PAR, designates the spectral range (wave band) of solar radiation from 400 to 700 nanometers that photosynthetic organisms are able to use in the process of photosynthesis. This spectral region corresponds more or less with the range of light visible to the human eye. Photons at shorter wavelengths tend to be so energetic that they can be damaging to cells and tissues, but are mostly filtered out by the ozone layer in the stratosphere. Photons at longer wavelengths do not carry enough energy to allow photosynthesis to
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Neritic zone


the following: The neritic zone is permanently covered with generally well-oxygenated water, receives plenty of sunlight and has low water pressure; moreover, it has relatively stable temperature, pressure, light and salinity levels, making it suitable for photosynthetic life. In particular, the benthic zone (shallow ocean floor) in the neritic is much more stable than in the intertidal zone. The above characteristics make the neritic zone the location of the majority of sea life. The result is high primary production by photosynthetic life such as phytoplankton
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Photosynthetic efficiency


one 700 nm photon from each one)br 30% of the in-band photons are lost due to incomplete absorption or photons hitting components other than chloroplastsbr 24% of the absorbed photon energy is lost due to degrading short wavelength photons to the 700 nm energy levelbr 68% of the utilized energy is lost in conversion into d-glucosebr 35–45% of the glucose is consumed by the leaf in the processes of dark and photo respiration Stated another way:br 100% sunlight → non-bioavailable photons waste is 47%, leavingbr
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Chemotroph


Chemotrophs are organisms that obtain energy by the oxidation of electron donors in their environments. These molecules can be organic (chemoorganotrophs) or inorganic (chemolithotrophs). The chemotroph designation is in contrast to phototrophs, which use solar energy. Chemotrophs can be either autotrophic or heterotrophic. Chemotrophs are found in ocean floors where sunlight cannot reach them because they are not dependent on solar energy. Ocean floors often contain underwater volcanos that can provide heat as a substitute for sunlight's warmth. Chemoautotrophs (or chemotrophic autotroph) ("Greek
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Lobophyllia corymbosa


hourglass and the polyps inside are thick and fleshy. They are normally retracted in the daytime but extend their tentacles at night to feed. The colour of the polyps is bluish or greenish-grey, or yellowish-brown. This colour is due to the zooxanthellae, the minute symbiotic dinoflagellates which reside within the tissues of the coral. These photosynthetic algae use sunlight to create organic compounds and the coral is able to use these as part of its nutritional needs. The type locality of "Lobophyllia corymbosa" is the Red Sea
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Kinetic Isotope Effects of RuBisCO


the required activation energy. The RuBisCOs used by varying photosynthetic organisms vary slightly in their enzyme structure, and this enzyme structure results in varying transition states. This diversity in enzyme structure is reflected in the resulting ΔC values measured from different photosynthetic organisms. However, overlap exists between the ΔC values of different groups because the carbon isotope values measured are generally of the entire organism, and not just its RuBisCO enzyme. Many other factors, including growth rate and the isotopic composition of the starting substrate, can affect the carbon isotope values
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Carbohydrate metabolism


Carbohydrate metabolism refers to various biochemical processes responsible for the metabolic formation, breakdown, and interconversion of carbohydrates in living organisms. Carbohydrates are central to many essential metabolic pathways. Plants synthesize carbohydrates from carbon dioxide and water through photosynthesis, allowing them to store energy absorbed from sunlight internally. When animals and fungi consume plants, they use cellular respiration to break down these stored carbohydrates to make energy available to cells. Both animals and plants temporarily store the released energy in the form of high energy molecules, such as ATP, for use
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Night


the morphology, physiology and behavior of almost every organism. Some animals sleep during the night, whilst other nocturnal animals including moths and crickets are active during this time. The effects of day and night are not seen in the animal kingdom alone; plants have also evolved adaptations to cope best with the lack of sunlight during this time. For example, crassulacean acid metabolism is a unique type of carbon fixation which allows photosynthetic plants to store carbon dioxide in their tissues as organic acids during the night, which can then be used
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Photosynthetic efficiency


The photosynthetic efficiency is the fraction of light energy converted into chemical energy during photosynthesis in plants and algae. Photosynthesis can be described by the simplified chemical reaction where CHO is glucose (which is subsequently transformed into other sugars, cellulose, lignin, and so forth). The value of the photosynthetic efficiency is dependent on how light energy is defined – it depends on whether we count only the light that is absorbed, and on what kind of light is used (see Photosynthetically active radiation). It takes eight (or perhaps
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Biological thermodynamics


No matter what the type of living species, all living organisms must capture, transduce, store, and use energy to live. The relationship between the energy of the incoming sunlight and its wavelength or frequency is given by where "h" is the Planck constant (6.63x10Js) and "c" is the speed of light (2.998x10 m/s). Plants trap this energy from the sunlight and undergo photosynthesis, effectively converting solar energy into chemical energy. To transfer the energy once again, animals will feed on plants
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List of Dutch discoveries


knowledge of Leeuwenhoek's work. Photosynthesis is a fundamental biochemical process in which plants, algae, and some bacteria convert sunlight to chemical energy. The process was discovered by Jan Ingenhousz in 1779. The chemical energy is used to drive reactions such as the formation of sugars or the fixation of nitrogen into amino acids, the building blocks for protein synthesis. Ultimately, nearly all living things depend on energy produced from photosynthesis. It is also responsible for producing the oxygen that makes animal life possible. Organisms that produce energy through photosynthesis
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Sustainable living


buying these renewable energy credits because it allows them to claim that they produce renewable energy). In some special cases, producing households may be paid up to four times the standard electricity rate, but this is not common. Solar power harnesses the energy of the sun to make electricity. Two typical methods for converting solar energy into electricity are photo-voltaic cells that are organized into panels and concentrated solar power, which uses mirrors to concentrate sunlight to either heat a fluid that runs an electrical generator via a steam turbine or
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Environmental issues in the Niger Delta


recent years it has found its way into the Niger River, choking out both sunlight and oxygen to the marine organisms that live there. When a species such as water hyacinth makes its way into the ecosystem, it competes with native plants for sunlight, diminishing energy resources within the marine environment. With the loss of energy some populations will not be able to survive, or their numbers may drop beyond a point of no return, creating a threatened environment. Added to the loss of energy, water hyacinth also takes up and
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Isopora palifera


live within the tissues of the coral polyps. These photosynthetic algae use sunlight to create organic compounds and the coral is able to use these to provide part of its nutritional needs. Fluorescent granules of pigment are present in the tissues and these are in greater concentrations in individuals growing in high-light environments. "Isopora palifera" closely resembles "Isopora cuneata", and often has similar forms of growth, but "I. cuneata" mostly occurs in more eastern parts of the Pacific and in shallower water, and the holes in
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Photosynthesis


The first photosynthetic organisms probably evolved early in the evolutionary history of life and most likely used reducing agents such as hydrogen or hydrogen sulfide, rather than water, as sources of electrons. Cyanobacteria appeared later; the excess oxygen they produced contributed directly to the oxygenation of the Earth, which rendered the evolution of complex life possible. Today, the average rate of energy capture by photosynthesis globally is approximately 130 terawatts, which is about eight times the current power consumption of human civilization. Photosynthetic organisms also convert around 100–115 billion tonnes (
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Crustose lichen


sites of lower aridity. The amount of sunlight that lichens receive determines the rate at which photosynthesis occurs. Moreover, surface area also influences photosynthetic rates. In high sunlight conditions, foliose lichens with broad lobes are prevalent. In comparison, crustose lichens have less surface area than foliose lichens and will tend to have slower photosynthetic rates. Generally, higher levels of sunlight promote growth of the crustose lichens. Extreme temperatures are unfavorable for the growth of crustose lichens. Temperatures below 0 °C can result in cessation of growth and thalli
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Solar chemical


Solar chemical refers to a number of possible processes that harness solar energy by absorbing sunlight in a chemical reaction. The idea is conceptually similar to photosynthesis in plants, which converts solar energy into the chemical bonds of glucose molecules, but without using living organisms, which is why it is also called artificial photosynthesis. A promising approach is to use focused sunlight to provide the energy needed to split water into its constituent hydrogen and oxygen in the presence of a metallic catalyst such as zinc. This is normally done in a two-
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Biological photovoltaics


through an external circuit to do useful work. It is hoped that using a living organism (which is capable of self-assembly and self-repair) as the light harvesting material, will make biological photovoltaics a cost-effective alternative to synthetic light-energy-transduction technologies such as silicon-based photovoltaics. Like other fuel cells, biological photovoltaic systems are divided into anodic and cathodic half-cells. Oxygenic photosynthetic biological material, such as purified photosystems or whole algal or cyanobacterial cells, are employed in the anodic half
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Metabolism


These include breaking down and oxidizing food molecules. The purpose of the catabolic reactions is to provide the energy and components needed by anabolic reactions which build molecules. The exact nature of these catabolic reactions differ from organism to organism, and organisms can be classified based on their sources of energy and carbon (their primary nutritional groups), as shown in the table below. Organic molecules are used as a source of energy by organotrophs, while lithotrophs use inorganic substrates, and phototrophs capture sunlight as chemical energy. However, all these
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Phototroph


a different meaning, the term took its current definition after Lwoff and collaborators (1946). Most of the well-recognized phototrophs are autotrophic, also known as photoautotrophs, and can fix carbon. They can be contrasted with chemotrophs that obtain their energy by the oxidation of electron donors in their environments. Photoautotrophs are capable of synthesizing their own food from inorganic substances using light as an energy source. Green plants and photosynthetic bacteria are photoautotrophs. Photoautotrophic organisms are sometimes referred to as holophytic. Such organisms derive their energy for food
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Solar–hydrogen energy cycle


to produce electricity, which can power the devices when sunlight is unavailable. The Solar–Hydrogen energy cycle can be incorporated using organic thin film solar cells and microcrystalline silicon thin film solar cells This cycle can also be incorporated using photoelectrochemical solar cells. These solar have been incorporated since 1972 for hydrogen production and is capable of directly converting sunlight into chemical energy. An aqueous solution of hydrogen iodide has been proposed as an alternative to water as a fuel that can be used in this cycle. Splitting of hydrogen iodide is easier than
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