query: during photosynthesis carbon dioxide combines with water in the presence of sunlight to form

pos: Photosynthesis Photosynthesis Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that can later be released to fuel the organisms' activities. This chemical energy is stored in carbohydrate molecules, such as sugars, which are synthesized from carbon dioxide and water – hence the name "photosynthesis", from the Greek φῶς, "phōs", "light", and σύνθεσις, "synthesis", "putting together". In most cases, oxygen is also released as a waste product. Most plants, most algae, and cyanobacteria perform photosynthesis; such organisms are called photoautotrophs. Photosynthesis is largely responsible for producing and maintaining the oxygen content of the

pos: Photosynthesis oxygenase activity is more commonly known as photorespiration, since it is characterized by light-dependent oxygen consumption and the release of carbon dioxide. Photosynthesis Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that can later be released to fuel the organisms' activities. This chemical energy is stored in carbohydrate molecules, such as sugars, which are synthesized from carbon dioxide and water – hence the name "photosynthesis", from the Greek φῶς, "phōs", "light", and σύνθεσις, "synthesis", "putting together". In most cases, oxygen is also released as a waste product. Most plants, most algae,

neg: Artificial photosynthesis developing its own artificial photosynthesis research by using sunlight, water and carbon dioxide to "create the carbon building blocks from which resins, plastics and fibers can be synthesized." This was confirmed with the establishment of the KAITEKI Institute later that year, with carbon dioxide reduction through artificial photosynthesis as one of the main goals. During 2010, the United States Department of Energy established, as one of its Energy Innovation Hubs, the Joint Center for Artificial Photosynthesis. The mission of JCAP is to find a cost-effective method to produce fuels using only sunlight, water, and carbon-dioxide as inputs. JCAP is managed

neg: Respiratory system also possess a heart that pumps blood containing hemocyanin as its oxygen-capturing molecule. Hence, this respiratory system is similar to that of vertebrate fish. The respiratory system of gastropods can include either gills or a lung. Plants use carbon dioxide gas in the process of photosynthesis, and exhale oxygen gas as waste. The chemical equation of photosynthesis is 6 CO (carbon dioxide) and 6 HO (water), which in the presence of sunlight makes CHO (glucose) and 6 O (oxygen). Photosynthesis uses electrons on the carbon atoms as the repository for the energy obtained from sunlight. Respiration is the opposite of

neg: Artificial photosynthesis Artificial photosynthesis Artificial photosynthesis is a chemical process that replicates the natural process of photosynthesis, a process that converts sunlight, water, and carbon dioxide into carbohydrates and oxygen; as an imitation of a natural process it is biomimetic. The term artificial photosynthesis is commonly used to refer to any scheme for capturing and storing the energy from sunlight in the chemical bonds of a fuel (a solar fuel). Photocatalytic water splitting converts water into hydrogen and oxygen and is a major research topic of artificial photosynthesis. Light-driven carbon dioxide reduction is another process studied that replicates natural carbon fixation. Research

neg: Artificial photosynthesis concentrations, something that artificial catalysts still cannot perform. Artificial photosynthesis Artificial photosynthesis is a chemical process that replicates the natural process of photosynthesis, a process that converts sunlight, water, and carbon dioxide into carbohydrates and oxygen; as an imitation of a natural process it is biomimetic. The term artificial photosynthesis is commonly used to refer to any scheme for capturing and storing the energy from sunlight in the chemical bonds of a fuel (a solar fuel). Photocatalytic water splitting converts water into hydrogen and oxygen and is a major research topic of artificial photosynthesis. Light-driven carbon dioxide reduction is another

neg: Irrigation in viticulture system of the vine may have difficulties absorbing these nutrients. Within the structure of the plant itself, water acts as a transport within the xylem to bring these nutrients to all ends of the plant. During the process of photosynthesis, water molecules combine with carbon derived from carbon dioxide to form glucose, which is the primary energy source of the vine, as well as oxygen as a by-product. In addition to its use in photosynthesis, a vine's water supply is also depleted by the processes of evaporation and transpiration. In evaporation, heat (aided by wind and sunlight) causes water in

neg: History of Earth for cells to derive energy from the Sun. Most 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 alternatives to hydrogen stripped from water

neg: Deep sea community maximum depth of . The sonar system uses phase and amplitude bottom detection, with an accuracy of better than 0.2% of water depth (this is an error of about 22 meters 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

neg: Photosynthesis type of photosynthesis used by living organisms. Although there are some differences between oxygenic photosynthesis in plants, algae, and cyanobacteria, the overall process is quite similar in these organisms. There are also many varieties of anoxygenic photosynthesis, used mostly by certain types of bacteria, which consume carbon dioxide but do not release oxygen. Carbon dioxide is converted into sugars in a process called carbon fixation; photosynthesis captures energy from sunlight to convert carbon dioxide into carbohydrate. Carbon fixation is an endothermic redox reaction. In general outline, photosynthesis is the opposite of cellular respiration: while photosyntesis is a process of reduction

neg: Glucose are termed glucans. Glucose is produced by plants through the photosynthesis using sunlight, water and carbon dioxide and can be used by all living organisms as an energy and carbon source. However, most glucose does not occur in its free form, but in the form of its polymers, i.e. lactose, sucrose, starch and others which are energy reserve substances, and cellulose and chitin, which are components of the cell wall in plants or fungi and arthropods, respectively. These polymers are degraded to glucose during food intake by animals, fungi and bacteria using enzymes. All animals are also able to produce

neg: Metabolism Autotrophs such as plants can construct the complex organic molecules in cells such as polysaccharides and proteins from simple molecules like carbon dioxide and water. Heterotrophs, on the other hand, require a source of more complex substances, such as monosaccharides and amino acids, to produce these complex molecules. Organisms can be further classified by ultimate source of 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

neg: Sugar Cane Growers Cooperative of Florida of the most efficient at converting carbon dioxide in sunlight and storing carbohydrate energy through photosynthesis. All green plants produce sugar (sucrose), but none as effectively as sugarcane. Water in the leaves and photosynthesis enable the plant to convert carbon dioxide from the air and radiation from the sun along with chlorophyll into sugar, which is stored in the stalk of the plant. Palm Beach County, Florida, home of the Cooperative, accounts for approximately 75 percent of the commercial sugarcane acreage in Florida and 75 percent of the total harvested sugarcane tonnage in Florida. Rich, organic soil, abundant water and

neg: Photosynthesis passed through a food chain. The fixation or reduction of carbon dioxide is a process in which carbon dioxide combines with a five-carbon sugar, ribulose 1,5-bisphosphate, to yield two molecules of a three-carbon compound, glycerate 3-phosphate, also known as 3-phosphoglycerate. Glycerate 3-phosphate, in the presence of ATP and NADPH produced during the light-dependent stages, is reduced to glyceraldehyde 3-phosphate. This product is also referred to as 3-phosphoglyceraldehyde (PGAL) or, more generically, as triose phosphate. Most (5 out of 6 molecules) of the glyceraldehyde 3-phosphate produced is used to regenerate ribulose 1,5-bisphosphate so the process can continue. The triose phosphates not

neg: Carbon dioxide aerobic fungi and bacteria. In vertebrates, the carbon dioxide travels in the blood from the body's tissues to the skin (e.g., amphibians) or the gills (e.g., fish), from where it dissolves in the water, or to the lungs from where it is exhaled. During active photosynthesis, plants can absorb more carbon dioxide from the atmosphere than they release in respiration. Carbon fixation is a biochemical process by which atmospheric carbon dioxide is incorporated by plants, algae and (cyanobacteria) into energy-rich organic molecules such as glucose, thus creating their own food by photosynthesis. Photosynthesis uses carbon dioxide and water to produce

neg: Zostera novazelandica can become an annual, where the species 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 significant negative effect on patch expansion. The

neg: Our Mr. Sun exactly sire how it works. They believe chlorophyll uses sunlight to combine carbon dioxide molecules with water molecules, along with salts, to create sugars and release oxygen. These sugars form the bulk of a plant including its fruit. Most of these plants are grown in the sea as phytoplankton, which is the food source of zooplankton, which are eaten by fish. All animals survive on food created by the Sun through photosynthesis; either directly by eating plants, or indirectly by eating animals that eat plants. The Sun provided the energy for photosynthesis through its light, which was created at the

neg: Joint Center for Artificial Photosynthesis time. At the California Institute of Technology, they're developing a way to turn sunlight and water into fuel for our cars". Joint Center for Artificial Photosynthesis The Joint Center for Artificial Photosynthesis (JCAP), founded in 2010, is a (DOE) Energy Innovation Hub whose primary mission is to find a cost-effective method to produce fuels using only sunlight, water, and carbon-dioxide. The program has a budget of $122M over five years, subject to Congressional appropriation. The Director of JCAP is Professor Harry Atwater of Caltech and its two main centers are located at the California Institute of Technology and the Lawrence

neg: C1 chemistry carbon monoxide, carbon dioxide, and methanol are converted to methane, provided suitable reducing agents. Methanogenesis by methanogenic archaea is reversible. In photosynthesis, carbon dioxide and water is converted to sugars (and O), the energy for this (thermally) uphill reaction being provided by sunlight. C1 chemistry C1 chemistry is the chemistry of one-carbon molecules. Although many compounds and ions contain only one carbon, stable and abundant C-1 feedstocks are the focus of research. Four compounds are of major industrial importance: methane, carbon monoxide, carbon dioxide, and methanol. Technologies that interconvert these species are often consequential. Carbon monoxide and methanol are important

neg: Limnology wind mixing can increase dissolved oxygen concentrations, particularly in surface waters of aquatic ecosystems. Because dissolved oxygen solubility is linked to water temperatures, changes in temperature affect dissolved oxygen concentrations; warmer water has a lower capacity to "hold" oxygen as colder water. Biologically, both photosynthesis and aerobic respiration affect dissolved oxygen concentrations. Photosynthesis by autotrophic organisms, such as phytoplankton and aquatic algae, increases dissolved oxygen concentrations while simultaneously reducing carbon dioxide concentrations, since carbon dioxide is taken up during photosynthesis. All aerobic organisms in the aquatic environment take up dissolved oxygen during aerobic respiration, while carbon dioxide is released as

neg: Environmental impact of biodiesel produces carbon dioxide emissions similar to those from ordinary fossil fuels, the plant feedstock used in the production absorbs carbon dioxide from the atmosphere when it grows. Plants absorb carbon dioxide through a process known as photosynthesis which allows it to store energy from sunlight in the form of sugars and starches. After the biomass is converted into biodiesel and burned as fuel the energy and carbon is released again. Some of that energy can be used to power an engine while the carbon dioxide is released back into the atmosphere. When considering the total amount of greenhouse gas emissions

neg: Period 2 element (including hydrogen, carbon, and sulfur). Many oxides are extremely stable substances difficult to decompose—like water, carbon dioxide, alumina, silica, and iron oxides (the latter often appearing as rust). Oxygen is part of substances best described as some salts of metals and oxygen-containing acids (thus nitrates, sulfates, phosphates, silicates, and carbonates. Oxygen is essential to all life. Plants and phytoplankton photosynthesize water and carbon dioxide and water, both oxides, in the presence of sunlight to form sugars with the release of oxygen. The sugars are then turned into such substances as cellulose and (with nitrogen and often sulfur) proteins and other

neg: Oxygen evolution Jan Ingenhousz, a Dutch physician, who showed that "restoration" of air only worked in the presence of light and green plant parts. Ingenhousz suggested in 1796 that CO (carbon dioxide) is split during photosynthesis to release oxygen, while the carbon combined with water to form carbohydrates. While this hypothesis was attractive and reasonable and thus widely accepted for a long time, it was later proven incorrect. Graduate student C.B. Van Niel at Stanford University found that purple sulfur bacteria reduce carbon to carbohydrates, but accumulate sulfur instead of releasing oxygen. He boldly proposed that, in analogy to the sulfur bacteria's

neg: Methanol economy more feasible due to its higher concentrations in dissolved form. This would allow the chemical recycling of CO, thus mimicking nature’s photosynthesis. In the process of photosynthesis, green plants use the energy of sunlight to split water into free oxygen (which is released) and free hydrogen. Rather than attempt to store the hydrogen, plants immediately capture carbon dioxide from the air to allow the hydrogen to reduce it to storable fuels such as hydrocarbons (plant oils and terpenes) and polyalcohols (glycerol, sugars and starches). In the methanol economy, any process which similarly produces free hydrogen, proposes to immediately use it

neg: Lake metabolism Lake metabolism Lake metabolism represents a lake ecosystem's balance between carbon fixation (gross primary production) and biological carbon oxidation (ecosystem respiration). Lake metabolism includes the carbon fixation and oxidation from all organism within the lake, from bacteria to fishes. Estimates of lake metabolism typically rely on the measurement of dissolved oxygen or carbon dioxide. Oxygen is produced and carbon dioxide consumed through photosynthesis and oxygen is consumed and carbon dioxide produced through respiration. Photosynthesis: formula_1 Respiration: formula_2 Photosynthesis and oxygen production only occurs in the presence of light, while the consumption of oxygen via respiration occurs in both the presence

neg: Carbon fixation 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 compounds are used by heterotrophs to produce energy and

neg: Excretion These are known as metabolism. These chemical reactions produce waste products such as carbon dioxide, water, salts, urea and uric acid. Accumulation of these wastes beyond a level inside the body is harmful to the body. The excretory organs remove these wastes. This process of removal of metabolic waste from the body is known as excretion. Green plants produce carbon dioxide and water as respiratory products. In green plants, the carbon dioxide released during respiration gets utilized during photosynthesis. Oxygen is a by product generated during photosynthesis, and exits through stomata, root cell walls, and other routes. Plants can get

neg: Artificial photosynthesis linked molecules. Research into finding catalysts that can convert water, carbon dioxide, and sunlight to carbohydrates or hydrogen is a current, active field. By studying the natural oxygen-evolving complex (OEC), researchers have developed catalysts such as the "blue dimer" to mimic its function or inorganic-based materials such as Birnessite with the similar building block as the OEC. Photoelectrochemical cells that reduce carbon dioxide into carbon monoxide (CO), formic acid (HCOOH) and methanol (CHOH) are under development. However, these catalysts are still very inefficient. Hydrogen is the simplest solar fuel to synthesize, since it involves only the transference of two electrons

neg: Chloroplast transformed into chemical energy, to subsequently produce food in the form of sugars. Water (HO) and carbon dioxide (CO) are used in photosynthesis, and sugar and oxygen (O) is made, using light energy. Photosynthesis is divided into two stages—the light reactions, where water is split to produce oxygen, and the dark reactions, or Calvin cycle, which builds sugar molecules from carbon dioxide. The two phases are linked by the energy carriers adenosine triphosphate (ATP) and nicotinamide adenine dinucleotide phosphate (NADP). The light reactions take place on the thylakoid membranes. They take light energy and store it in NADPH, a form

neg: Polar forests of the Cretaceous main factors that contribute to net forest productivity: carbon dioxide concentration, root respiration rates, temperature and photosynthesis. Carbon dioxide alone tends to decrease leaf and root respiration by lowering the light compensation point of photosynthesis, allowing for a net positive gain in carbon intake during the course of a day. The reduction of root respiration tends to initiate root growth and ultimately results in an improvement in nutrient and water uptake efficiency. When photosynthesis is added to the effects of carbon dioxide, depending on regional temperature, forest productivity is drastically increased. The combination of all four physiological factors results in

neg: BIOS-3 'phytrons' contributed approximately 25% of the air filtering in the compound. Later the algal cultivator was converted into a third phytron. A level of light comparable to sunlight was supplied in each of the by xenon lamps, cooled by water jackets. The facility used of electricity, supplied by a nearby hydroelectric power station. Chlorella algae were used to recycle air breathed by humans, absorbing carbon dioxide and replenishing it with oxygen through photosynthesis. The algae were cultivated in stacked tanks under artificial light. To achieve a balance of oxygen and carbon dioxide, one human needed of exposed Chlorella. Air was

neg: Algal mat that the bacteria started life on Earth during the Pre-Cambrian age. Fossilized cyanobacteria are commonly found in rocks that date back to Mesoproterozoic. Cyanobacteria are photoautotroph in nature; meaning they convert carbon dioxide and absorbed sunlight into food and energy via photosynthesis. They are also able to fix atmospheric nitrogen and convert it into the biologically-usable form (Paerl, Pinkney and Steppe, 2000). This gives them competitive advantage over other organisms that may be limited by the shortage of biologically available nitrogen. The cyanobacteria colonies contain two types of cells, the regular cells with chlorophyll carrying out the photosynthesis, and heterocysts

neg: Xerophyte growth, it is vital that the plant has a very efficient photosynthesis system which maximises the utilisation of the little carbon dioxide the plant gets. Many succulent xerophytes employ the Crassulacean acid metabolism or better known as CAM photosynthesis. It is also dubbed the "dark" carboxylation mechanism because plants in arid regions collect carbon dioxide at night when the stomata open, and store the gases to be used for photosynthesis in the presence of light during the day. Although most xerophytes are quite small, this mechanism allows a positive carbon balance in the plants to sustain life and growth. Prime

neg: Coral reef the form of glucose, glycerol and amino acids. Because of this relationship, coral reefs grow much faster in clear water, which admits more sunlight. Without their symbionts, coral growth would be too slow to form significant reef structures. Corals get up to 90% of their nutrients from their symbionts. In return, as an example of mutualism, the corals shelter the zooxanthellae, averaging one million for every cubic centimeter of coral, and provide a constant supply of the carbon dioxide they need for photosynthesis. The varying pigments in different species of zooxanthellae give them an overall brown or golden-brown appearance, and

neg: Cactus allows them to expand and contract easily for quick water absorption after rain, followed by long drought periods. Like other succulent plants, most cacti employ a special mechanism called "crassulacean acid metabolism" (CAM) as part of photosynthesis. Transpiration, during which carbon dioxide enters the plant and water escapes, does not take place during the day at the same time as photosynthesis, but instead occurs at night. The plant stores the carbon dioxide it takes in as malic acid, retaining it until daylight returns, and only then using it in photosynthesis. Because transpiration takes place during the cooler, more humid night

neg: Photosynthesis of carbon dioxide to carbohydrate, cellular respiration is the oxidation of carbohydrate or other nutrients 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 metabolism. Photosynthesis and cellular respiration are distinct processes, as they take place through different sequences of chemical reactions and in different cellular compartments. The general equation for photosynthesis as first proposed by Cornelis van Niel is therefore: Since water is used as the electron donor in oxygenic photosynthesis, the equation for

neg: Artificial photosynthesis of this topic includes the design and assembly of devices for the direct production of solar fuels, photoelectrochemistry and its application in fuel cells, and the engineering of enzymes and photoautotrophic microorganisms for microbial biofuel and biohydrogen production from sunlight. The photosynthetic reaction can be divided into two half-reactions of oxidation and reduction, both of which are essential to producing fuel. In plant photosynthesis, water molecules are photo-oxidized to release oxygen and protons. The second phase of plant photosynthesis (also known as the Calvin-Benson cycle) is a light-independent reaction that converts carbon dioxide into glucose (fuel). Researchers of artificial photosynthesis

neg: BioFields (company) of dry, non-arable land. BioFields’ technology Direct to Ethanol uses non-toxic blue-green algae to produce biofuels in a fully enclosed secure system. This technology optimizes the metabolism of blue-green algae creating a new pathway for the use and fixation of carbon resulting in the synthesis of ethanol. The blue-green algae proliferates rapidly and uses efficiently sunlight, carbon dioxide and inorganic elements, for the production of ethanol or other biofuels. The capture of carbon dioxide allows to accelerate the process of photosynthesis using the blue-green algae to convert the sun's energy in the form of intracellular sugar, which provides vital energy

neg: Energy development the globe, world grain production increased by 250%. The energy for the Green Revolution was provided by fossil fuels in the form of fertilizers (natural gas), pesticides (oil), and hydrocarbon fueled irrigation. The peaking of world hydrocarbon production (peak oil) may lead to significant changes, and require sustainable methods of production. One vision of a sustainable energy future involves all human structures on the earth's surface (i.e., buildings, vehicles and roads) doing artificial photosynthesis (using sunlight to split water as a source of hydrogen and absorbing carbon dioxide to make fertilizer) efficiently than plants. With contemporary space industry's economic activity

neg: Photosynthesis is about three times the current power consumption of human civilization. Photosynthetic organisms also convert around 100–115 billion tonnes (91-104 petagrams) of carbon into biomass per year. Photosynthetic organisms are photoautotrophs, which means that they are able to synthesize 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; photoheterotrophs use organic compounds, rather than carbon dioxide, as a source of carbon. In plants, algae, and cyanobacteria, photosynthesis releases oxygen. This is called "oxygenic photosynthesis" and is by far the most common

neg: Water splitting to replicate the natural process of photosynthesis, converting sunlight, water and carbon dioxide into carbohydrates and oxygen. Recently, this has been successful in splitting water into hydrogen and oxygen using an artificial compound called Nafion. High-temperature electrolysis (also HTE or steam electrolysis) is a method currently being investigated for the production of hydrogen from water with oxygen as a by-product. Other research includes thermolysis on defective carbon substrates, thus making hydrogen production possible at temperatures just under 1000 °C. The iron oxide cycle is a series of thermochemical processes used to produce hydrogen. The iron oxide cycle consists of two

neg: Xerophyte conversion of violaxanthin to zeaxanthin. These two molecules are photo-protective molecules. Under high light, it is unfavourable to channel extra light into photosynthesis because excessive light may cause damage to the plant proteins. Zeaxanthin dissociates light-channelling from the photosynthesis reaction - light energy in the form of photons will not be transmitted into the photosynthetic pathway anymore. Stomata closure not only restricts the movement of water out of the plant, another consequence of the phenomenon is that carbon dioxide influx or intake into the plant is also reduced. As photosynthesis requires carbon dioxide as a substrate to produce sugar for

neg: Spawn (biology) sunset time, and possibly chemical signalling. Synchronous spawning may form hybrids and is perhaps involved in coral speciation. In some places the spawn can be visually dramatic, clouding the usually clear water with gametes, typically at night. Corals use two methods for sexual reproduction, which differ in whether the female gametes are released: Fungi are not plants, and require different conditions for optimal growth. Plants develop through photosynthesis, a process that converts atmospheric carbon dioxide into carbohydrates, especially cellulose. While sunlight provides an energy source for plants, mushrooms derive all of their energy and growth materials from their growth medium,

neg: Atmospheric carbon cycle Large amounts of carbon dioxide are dissolved in cold water in higher latitudes. This water sinks down and brings the carbon into the deeper ocean levels, where it can stay for anywhere between decades and several centuries. Ocean circulation events cause this process to be variable. For example, during El Nino events there is less deep ocean upwelling, leading to lower outgasing of carbon dioxide into the atmosphere. Biological processes also lead to ocean-atmosphere carbon exchange. Carbon dioxide equilibriates between the atmosphere and the ocean's surface layers. As autotrophs add or subtract carbon dioxide from the water through photosynthesis or

neg: Photosynthesis the "light-independent reactions" use these products to capture and reduce carbon dioxide. Most organisms that utilize oxygenic photosynthesis use visible light for the light-dependent reactions, although at least three use shortwave infrared or, more specifically, far-red radiation. 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

neg: Algae bioreactor 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 for photosynthesis: Some of the first experiments with the aim of cultivating algae were conducted in 1957 by the "Carnegie Institution" in Washington. In

neg: Embryophyte eukaryotes with specialized reproductive organs. The name derives from their innovative characteristic of nurturing the young embryo sporophyte during the early stages of its multicellular development within the tissues of the parent gametophyte. With very few exceptions, embryophytes obtain their energy by photosynthesis, that is by using the energy of sunlight to synthesize their food from carbon dioxide and water. The evolutionary origins of the embryophytes are discussed further below, but they are believed to have evolved from within a group of complex green algae during the Paleozoic era (which started around ) probably from terrestrial unicellular charophytes, similar to

neg: Carbohydrate metabolism Carbohydrate metabolism 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 in various cellular processes. Although humans consume a variety of carbohydrates, digestion

neg: Botany Earth by generating a large proportion of the oxygen and food that provide humans and other organisms with aerobic respiration with the chemical energy they need to exist. Plants, algae and cyanobacteria are the major groups of organisms that carry out photosynthesis, a process that uses the energy of 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. As a by-product of photosynthesis, plants release oxygen into the atmosphere, a gas that is required by nearly

neg: Plant specimens may be cut and polished using lapidary equipment. Fossil forests of petrified wood have been found in all continents. Fossils of seed ferns such as "Glossopteris" are widely distributed throughout several continents of the Southern Hemisphere, a fact that gave support to Alfred Wegener's early ideas regarding Continental drift theory. Most of the solid material in a plant is taken from the atmosphere. Through the process of photosynthesis, most plants use the energy in sunlight to convert carbon dioxide from the atmosphere, plus water, into simple sugars. These sugars are then used as building blocks and form the main

neg: Joint Center for Artificial Photosynthesis Joint Center for Artificial Photosynthesis The Joint Center for Artificial Photosynthesis (JCAP), founded in 2010, is a (DOE) Energy Innovation Hub whose primary mission is to find a cost-effective method to produce fuels using only sunlight, water, and carbon-dioxide. The program has a budget of $122M over five years, subject to Congressional appropriation. The Director of JCAP is Professor Harry Atwater of Caltech and its two main centers are located at the California Institute of Technology and the Lawrence Berkeley National Laboratory. In addition, JCAP has partners from Stanford University, the University of California at Berkeley, University of California at

neg: Chemical change all the process involved in photosynthesis, a process in which carbon dioxide and water are changed into sugars and oxygen by plants, digestion in which energy rich materials are used by organisms to grow and move, Krebs cycle which liberates energy from stored reserves, protein synthesis which enable organisms to grow using processes controlled by RNA etc. The following can indicate that a chemical change has taken place, although this evidence is not conclusive: Chemical change Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or

neg: Deforestation emissions with a range from 6 to 17%. Deforestation causes carbon dioxide to linger in the atmosphere. As carbon dioxide accrues, it produces a layer in the atmosphere that traps radiation from the sun. The radiation converts to heat which causes global warming, which is better known as the greenhouse effect. Plants remove carbon in the form of carbon dioxide from the atmosphere during the process of photosynthesis, but release some carbon dioxide back into the atmosphere during normal respiration. Only when actively growing can a tree or forest remove carbon, by storing it in plant tissues. Both the decay

neg: Susan Golden UCSD in 2008, Susan Golden's research converged with that of her husband, James Golden, to investigate biofuels. She is conducting research that investigates the usage of cyanobacteria for industrial purposes. Cyanobacteria are an attractive model organism due to simplistic genomes and their use of photosynthesis, and they could be used to replace petroleum fuels in the future through generation of biofuels. Cyanobacteria also grow fast and fix atmospheric carbon, converting carbon dioxide into biomass, which can then be converted to bio-oils and biofuels. They only require sunlight, water and inorganic trace elements for growth, and direct fixation of carbon for

neg: Glucose 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 and in animals as glycogen. Glucose circulates in the blood

neg: Photosynthesis plant. In 1778, Jan Ingenhousz, repeated Priestley's experiments. He discovered that it was the influence of sunlight on the plant that could cause it to revive a mouse in a matter of hours. In 1796, Jean Senebier, a Swiss pastor, botanist, and naturalist, demonstrated that green plants consume carbon dioxide and release oxygen under the influence of light. Soon afterward, Nicolas-Théodore de Saussure showed that the increase in mass of the plant as it grows could not be due only to uptake of CO but also to the incorporation of water. Thus, the basic reaction by which photosynthesis is used

neg: Carbon dioxide in Earth's atmosphere Carbon dioxide in Earth's atmosphere Carbon dioxide () is an important trace gas in Earth's atmosphere. It is an integral part of the carbon cycle, a biogeochemical cycle in which carbon is exchanged between the Earth's oceans, soil, rocks and the biosphere. Plants and other photoautotrophs use solar energy to produce carbohydrate from atmospheric carbon dioxide and water by photosynthesis. Almost all other organisms depend on carbohydrate derived from photosynthesis as their primary source of energy and carbon compounds. absorbs and emits infrared radiation at wavelengths of 4.26 µm (asymmetric stretching vibrational mode) and 14.99 µm (bending vibrational mode) and

neg: Cactus These strategies included being able to respond rapidly to periods of rain, and keeping transpiration low by using water very efficiently during photosynthesis. The latter was achieved by tightly controlling the opening of stomata. Like "Pereskia" species today, early ancestors may have been able to switch from the normal C mechanism, where carbon dioxide is used continuously in photosynthesis, to CAM cycling, in which when the stomata are closed, carbon dioxide produced by respiration is stored for later use in photosynthesis. "Pereskia" clade B marks the beginnings of an evolutionary switch to using stems as photosynthetic organs. Stems have stomata

neg: Microbial mat but the development of photosynthesis allow mats to proliferate outside of these environments by utilizing a more widely available energy source, sunlight. The final and most significant stage of this liberation was the development of oxygen-producing photosynthesis, since the main chemical inputs for this are carbon dioxide and water. As a result, microbial mats began to produce the atmosphere we know today, in which free oxygen is a vital component. At around the same time they may also have been the birthplace of the more complex eukaryote type of cell, of which all multicellular organisms are composed. Microbial mats were

neg: Darwin (spacecraft) in the atmosphere could be evidence for life. Oxygen is very reactive so if large amounts of oxygen exist in a planet's atmosphere some process such as photosynthesis must be continuously producing it. The presence of oxygen alone, however, is not conclusive evidence for life. Jupiter's moon Europa, for example, has a tenuous oxygen atmosphere thought to be produced by radiolysis of water molecules. Numerical simulations have shown that under proper conditions it is possible to build up an oxygen atmosphere via photolysis of carbon dioxide. Photolysis of water vapor and carbon dioxide produces hydroxyl ions and atomic oxygen, respectively,

neg: Carbon dioxide in Earth's atmosphere satellite to successfully achieve orbit in 2009. NASA's OCO-2 launched in 2014 was the second. Various other satellites missions to measure atmospheric X are planned. Carbon dioxide in Earth's atmosphere Carbon dioxide () is an important trace gas in Earth's atmosphere. It is an integral part of the carbon cycle, a biogeochemical cycle in which carbon is exchanged between the Earth's oceans, soil, rocks and the biosphere. Plants and other photoautotrophs use solar energy to produce carbohydrate from atmospheric carbon dioxide and water by photosynthesis. Almost all other organisms depend on carbohydrate derived from photosynthesis as their primary source of

neg: Zostera novazelandica reduction of seagrass is associated with the decline of both black swans and fish catches. As primary producers, they are needed to create organic form through photosynthesis using carbon dioxide and sunlight. They are large suppliers of resources in the food web. The seagrass are seabed stabilizers that promote biodiversity. Many young fish rely on the seagrass as nurseries to grow within during their juvenile months. For example, the New Zealand snapper, an important large fish for commercial and recreational purposes, relies on seagrass such as "Zostera novazelandica" as a nursery for the first year of their lives. There is

neg: Melvin Calvin a plant during photosynthesis, starting from its absorption as atmospheric carbon dioxide to its conversion into carbohydrates and other organic compounds. In doing so, Calvin, Benson and Bassham showed that sunlight acts on the chlorophyll in a plant to fuel the manufacturing of organic compounds, rather than on carbon dioxide as was previously believed. Calvin was the sole recipient of the 1961 Nobel Prize for Chemistry for what is sometimes known as the Calvin–Benson–Bassham Cycle. Calvin wrote an autobiography three decades later titled "Following the Trail of Light: A Scientific Odyssey". During the 1950s he was among the first members

neg: Redox of NADH to NAD). Photosynthesis and cellular respiration are complementary, but photosynthesis is not the reverse of the redox reaction in cell respiration: Biological energy is frequently stored and released by means of redox reactions. Photosynthesis involves the reduction of carbon dioxide into sugars and the oxidation of water into molecular oxygen. The reverse reaction, respiration, oxidizes sugars to produce carbon dioxide and water. As intermediate steps, the reduced carbon compounds are used to reduce nicotinamide adenine dinucleotide (NAD) to NADH, which then contributes to the creation of a proton gradient, which drives the synthesis of adenosine triphosphate (ATP) and

neg: Glucose be quantified. Glucose uptake in cells of organisms is measured with 2-deoxy-D-glucose or fluorodeoxyglucose. (F)fluorodeoxyglucose is used as a tracer in positron emission tomography in oncology and neurology, where it is by far the most commonly used diagnostic agent. 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

neg: Ocean acidification in the Arctic Ocean air-sea gas exchange with carbon dioxide. With less water completely exposed to the atmosphere, the levels of carbon dioxide gas in the water remain low. The Arctic ocean should have low carbon dioxide levels due to intense cooling, run off of fresh water and photosynthesis from marine organisms. However, the decrease of sea ice over the years due to global warming has limited freshwater runoff and has exposed a higher percentage of the ocean surface to the atmosphere. The increase of carbon dioxide in the water decreases the pH of the ocean causing ocean acidification. The decrease in sea ice

neg: Stromatolite Oxygenation Event). Cyanobacteria use water, carbon dioxide, and sunlight to create their food. A layer of mucus often forms over mats of cyanobacterial cells. In modern microbial mats, debris from the surrounding habitat can become trapped within the mucus, which can be cemented together by the calcium carbonate to grow thin laminations of limestone. These laminations can accrete over time, resulting in the banded pattern common to stromatolites. The domal morphology of biological stromatolites is the result of the vertical growth necessary for the continued infiltration of sunlight to the organisms for photosynthesis. Layered spherical growth structures termed oncolites are

neg: Carbon dioxide in Earth's atmosphere able to synthesize food directly from and water using energy from light. However, not all organisms that use light as a source of energy carry out photosynthesis, since "photoheterotrophs" use organic compounds, rather than , as a source of carbon. In plants, algae and cyanobacteria, photosynthesis releases oxygen. This is called "oxygenic photosynthesis". Although there are some differences between oxygenic photosynthesis in plants, algae, and cyanobacteria, the overall process is quite similar in these organisms. However, there are some types of bacteria that carry out anoxygenic photosynthesis, which consumes but does not release oxygen. Carbon dioxide is converted into sugars

neg: Nicolas-Théodore de Saussure mineral substances in plants arose from vague "transmutations" within the plant. His work enabled completion of the basic, overall chemical equation of photosynthesis, according to which carbon dioxide and water, in the presence of light, are converted by a green plant into fixed carbon (such as glucose, food for the plant), with gaseous oxygen released as a byproduct. Based on his accomplishments in plant chemistry and physiology, Saussure is considered the last of the major early pioneers of photosynthesis research, completing the work begun by his predecessors, including Jan van Helmont, Joseph Priestley, Jan Ingen-Housz, and Jean Senebier. For the

neg: C3 carbon fixation roots to transpiration. Examples include rice and barley. The isotopic signature of plants shows higher degree of C depletion than the plants, due to variation in fractionation of carbon isotopes in oxygenic photosynthesis across plant types. C3 carbon fixation This reaction occurs in all plants as the first step of the Calvin–Benson cycle. In plants, carbon dioxide is drawn out of malate and into this reaction rather than directly from the air. Plants that survive solely on fixation ( plants) tend to thrive in areas where sunlight intensity is moderate, temperatures are moderate, carbon dioxide concentrations are around 200 ppm

neg: Water splitting defined thermal gradient and the fast diffusion of hydrogen. With concentrated sunlight as heat source and only water in the reaction chamber, the produced gases are very clean with the only possible contaminant being water. A "Solar Water Cracker" with a concentrator of about 100 m² can produce almost one kilogram of hydrogen per sunshine hour. Research is being conducted over photocatalysis, the acceleration of a photoreaction in the presence of a catalyst. Its comprehension has been made possible ever since the discovery of water electrolysis by means of the titanium dioxide. Artificial photosynthesis is a research field that attempts

neg: Algal bloom colloquially as red tides. Freshwater algal blooms are the result of an excess of nutrients, particularly some phosphates. The excess of nutrients may originate from fertilizers that are applied to land for agricultural or recreational purposes. They may also originate from household cleaning products containing phosphorus. These nutrients can then enter watersheds through water runoff. Excess carbon and nitrogen have also been suspected as causes. Presence of residual sodium carbonate acts as catalyst for the algae to bloom by providing dissolved carbon dioxide for enhanced photosynthesis in the presence of nutrients. When phosphates are introduced into water systems, higher concentrations

neg: Moss (non-woody) plants that absorb water and nutrients mainly through their leaves and harvest carbon dioxide and sunlight to create food by photosynthesis. They differ from vascular plants in lacking water-bearing xylem tracheids or vessels. As in liverworts and hornworts, the haploid gametophyte generation is the dominant phase of the life cycle. This contrasts with the pattern in all vascular plants (seed plants and pteridophytes), where the diploid sporophyte generation is dominant. Mosses reproduce using spores, not seeds, and have no flowers. Moss gametophytes have stems which may be simple or branched and upright or prostrate. Their leaves are simple, usually

neg: Justus von Liebig had identified carbon, hydrogen, oxygen, and nitrogen as important, but disagreed over their sources and mechanisms of action. Carbon dioxide was known to be taken in and oxygen released during photosynthesis, but researchers suggested that oxygen was obtained from carbon dioxide, rather than from water. Hydrogen was believed to come primarily from water. Researchers disagreed about whether sources of carbon and nitrogen were atmospheric or soil-based. Nicolas-Théodore de Saussure's experiments, reported in "Recherches Chimiques sur la Végétation" (1804), suggested that carbon was obtained from atmospheric rather than soil-based sources, and that water was a likely source of hydrogen. He also

neg: Hill reaction the British biochemist Robin Hill. He demonstrated that isolated chloroplasts would make oxygen (O) but not fix carbon dioxide (CO). This is evidence that the light and dark reactions happen in different places within the cell. The Hill reaction of photosynthesis was discovered by Robin Hill (1937). He found that isolated chloroplasts from plants can release oxygen when they are illuminated by sunlight in the presence of a suitable electron acceptor such as ferricyanide. To demonstrate the Hill reaction in the laboratory dichlorophenolindophenol (DCPIP) was used as the terminal electron acceptor, replacing NADP which was not available due to the

neg: Oxygen makes up almost half of the Earth's crust. Dioxygen is used in cellular respiration and many major classes of organic molecules in living organisms contain oxygen, such as proteins, nucleic acids, carbohydrates, and fats, as do the major constituent inorganic compounds of animal shells, teeth, and bone. 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

neg: Anabaena circinalis On the " A. circinalis " filament, the most numerous structures are vegetative cells, responsible for the photosynthesis of high-energy sugars from environmental carbon, water, and sunlight. The energy from photosynthesis is used, in part, for the biosynthesis of cellular materials from nitrogenous compounds. During periods when combined nitrogen (e.g. ammonia or nitrate) is unavailable, " A. circinalis " form heterocysts, larger, round, nitrogen-fixing cells found every ten to twenty cells or so on the filament. Heterocysts function to convert environmental nitrogen (N) into compounds such as ammonia or nitrate. Nitrogenase, an oxygen-sensitive enzyme, is essential to this conversion. For

neg: Carbon cycle atmosphere exists in two main forms: carbon dioxide and methane. Both of these gases absorb and retain heat in the atmosphere and are partially responsible for the greenhouse effect. Methane produces a larger greenhouse effect per volume as compared to carbon dioxide, but it exists in much lower concentrations and is more short-lived than carbon dioxide, making carbon dioxide the more important greenhouse gas of the two. Carbon dioxide is removed from the atmosphere primarily through photosynthesis and enters the terrestrial and oceanic biospheres. Carbon dioxide also dissolves directly from the atmosphere into bodies of water (ocean, lakes, etc.), as

neg: Goldschmidt classification respect to nitrogen and oxygen. Consequently, with the development of free oxygen through photosynthesis, ammonia was oxidised to molecular nitrogen which has come to form four-fifths of the Earth's atmosphere. Carbon is also classed as an atmophile because it forms very strong multiple bonds with oxygen in carbon monoxide (slowly oxidised in the atmosphere) and carbon dioxide. The latter is the fourth-largest constituent of the Earth's atmosphere, while carbon monoxide occurs naturally in volcanoes and has a residence time in the atmosphere of a few months. Hydrogen, which occurs in the compound water, is also classed as an atmophile. Water

neg: Ocean acidification run off of fresh water and photosynthesis from marine organisms. However, the decrease of sea ice over the years due to global warming has limited freshwater runoff and has exposed a higher percentage of the ocean surface to the atmosphere. The increase of carbon dioxide in the water decreases the pH of the ocean causing ocean acidification. The decrease in sea ice has also allowed more Pacific water to flow into in the Arctic ocean during the winter, this is called Pacific winter water. The Pacific water flows into the Arctic ocean carrying additional amounts of carbon dioxide by being

neg: Climate change and potatoes concentrations in the atmosphere. The major benefit of increased atmospheric carbon dioxide for potatoes (and other plants) is an increase in their photosynthetic rates which can increase their growth rates. Potato crop yields are also predicted to benefit because potatoes partition more starch to the edible tubers under elevated carbon dioxide levels. Higher levels of atmospheric carbon dioxide also results in potatoes having to open their stomata less to take up an equal amount of carbon dioxide for photosynthesis, which means less water loss through transpiration from stomata. As a result, the water use efficiency (the amount of carbon assimilated

neg: Chlorella Chlorella Chlorella is a genus of single-celled green algae belonging to the division Chlorophyta. It is spherical in shape, about 2 to 10 μm in diameter, and is without flagella. "Chlorella" contains the green photosynthetic pigments chlorophyll-a and -b in its chloroplast. Through photosynthesis, it multiplies rapidly, requiring only carbon dioxide, water, sunlight, and a small amount of minerals to reproduce. The name "Chlorella" is taken from the Greek χλώρος, "chloros", meaning green, and the Latin diminutive suffix "ella", meaning small. German biochemist and cell physiologist Otto Heinrich Warburg, awarded with the Nobel Prize in Physiology or Medicine in 1931

neg: Plant nutrition supply from the carbon dioxide in the air by the process of photosynthesis. Each of these nutrients is used in a different place for a different essential function. Carbon forms the backbone of most plant biomolecules, including proteins, starches and cellulose. Carbon is fixed through photosynthesis; this converts carbon dioxide from the air into carbohydrates which are used to store and transport energy within the plant. Hydrogen also is necessary for building sugars and building the plant. It is obtained almost entirely from water. Hydrogen ions are imperative for a proton gradient to help drive the electron transport chain in

neg: Gas exchange roles of carbon dioxide, oxygen and water vapor. is the only carbon source for autotrophic growth by photosynthesis, and when a plant is actively photosynthesising in the light, it will be taking up carbon dioxide, and losing water vapor and oxygen. At night, plants respire, and gas exchange partly reverses: water vapor is still lost (but to a smaller extent), but oxygen is now taken up and carbon dioxide released. Plant gas exchange occurs mostly through the leaves. Gases diffuse into and out of the intercellular spaces within the leaf through pores called stomata, which are typically found on the

neg: Stoma a key reactant in photosynthesis, is present in the atmosphere at a concentration of about 400 ppm. Most plants require the stomata to be open during daytime. The air spaces in the leaf are saturated with water vapour, which exits the leaf through the stomata; this is known as transpiration. Therefore, plants cannot gain carbon dioxide without simultaneously losing water vapour. Ordinarily, carbon dioxide is fixed to ribulose-1,5-bisphosphate (RuBP) by the enzyme RuBisCO in mesophyll cells exposed directly to the air spaces inside the leaf. This exacerbates the transpiration problem for two reasons: first, RuBisCo has a relatively low affinity

neg: Fractionation of carbon isotopes in oxygenic photosynthesis characterization of food chains. Oxygenic photosynthesis is a metabolic pathway facilitated by autotrophs, including plants, algae, and cyanobacteria. This pathway converts inorganic carbon dioxide from the atmosphere or aquatic environment into carbohydrates, using water and energy from light, then releases molecular oxygen as a product. Organic carbon contains less of the stable isotope Carbon-13, or C, relative to the initial inorganic carbon from the atmosphere or water because photosynthetic carbon fixation involves several fractionating reactions with kinetic isotope effects. These reactions undergo a kinetic isotope effect because they are limited by overcoming an activation energy barrier. The lighter isotope has

neg: Bicarbonate indicator from red to magenta and, in relatively very low carbon dioxide concentrations, to purple. Carbon dioxide, even in the concentrations found in exhaled air, will dissolve in the indicator to form carbonic acid, a weak acid, which will lower the pH and give the characteristic colour change. A colour change to purple during photosynthesis shows a reduction in the percentage of carbon dioxide and is sometimes inferred as production of oxygen, but there is not actually any direct evidence for it. Great care must be taken to avoid acidic or alkaline contamination of the apparatus in such experiments, since the

neg: Calcium carbonate with the molar concentration of dissolved CO cannot exceed the value of "K". This seemingly simple solubility equation, however, must be taken along with the more complicated equilibrium of carbon dioxide with water (see carbonic acid). Some of the CO combines with H in the solution according to: HCO is known as the bicarbonate ion. Calcium bicarbonate is many times more soluble in water than calcium carbonate—indeed it exists "only" in solution. Some of the HCO combines with H in solution according to: Some of the HCO breaks up into water and dissolved carbon dioxide according to: And dissolved carbon

neg: Fractionation of carbon isotopes in oxygenic photosynthesis Calvin cycle during the day, when stomata are closed to prevent water loss, and the light reactions can drive the necessary ATP and NADPH production. This pathway differs from C4 photosynthesis because CAM plants separate carbon by storing fixed CO in vesicles at night, then transporting it for use during the day. Thus, CAM plants temporally concentrate CO to improve Rubsico efficiency, whereas C4 plants spatially concentrate CO in bundle sheath cells. The distribution of plants which use CAM photosynthesis includes epiphytes (e.g., orchids, bromeliads) and xerophytes (e.g., succulents, cacti). In Crassulacean acid metabolism, isotopic fractionation combines the effects of

neg: Carbon dioxide in Earth's atmosphere may have been higher, with estimated partial pressure as large as , because there was no bacterial photosynthesis to reduce the gas to carbon compounds and oxygen. Methane, a very active greenhouse gas which reacts with oxygen to produce and water vapor, may have been more prevalent as well, with a mixing ratio of 10 (100 parts per million by volume). Though water is responsible for most (about 36-70%) of the total greenhouse effect, the role of water vapor as a greenhouse gas depends on temperature. On Earth, carbon dioxide is the most relevant, direct anthropologically influenced greenhouse gas. Carbon

neg: E-diesel and other materials from water, carbon dioxide, and sunlight. There are other initiatives to create synthetic fuel from carbon dioxide and water, however they are not part of Audi's initiatives and the fuels are not called e-diesel. The water splitting methods vary. The U.S. Naval Research Laboratory (NRL) is designing a power-to-liquids system using the Fischer-Tropsch Process to create fuel on board a ship at sea, with the base products carbon dioxide (CO) and water (HO) being derived from sea water via "An Electrochemical Module Configuration For The Continuous Acidification Of Alkaline Water Sources And Recovery Of CO With Continuous

neg: Fossil not have been the only factor in the reduction in stromatolite abundance. Factors such as the chemistry of the environment may have been responsible for changes. While prokaryotic cyanobacteria themselves reproduce asexually through cell division, they were instrumental in priming the environment for the evolutionary development of more complex eukaryotic organisms. Cyanobacteria (as well as extremophile Gammaproteobacteria) are thought to be largely responsible for increasing the amount of oxygen in the primeval earth's atmosphere through their continuing photosynthesis. Cyanobacteria use water, carbon dioxide and sunlight to create their food. A layer of mucus often forms over mats of cyanobacterial cells.

neg: Chloroplast 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 from one, in unicellular algae, up to 100 in plants

neg: Deaerator Deaerator A deaerator is a device that removes oxygen and other dissolved gases from water, such as feedwater for steam-generating boilers. Dissolved oxygen in feedwater will cause serious corrosion damage in a boiler by attaching to the walls of metal piping and other equipment and forming oxides (rust). Dissolved carbon dioxide combines with water to form carbonic acid that causes further corrosion. Most deaerators are designed to remove oxygen down to levels of 7 ppb by weight (0.005 cm³/L) or less, as well as essentially eliminating carbon dioxide. Deaerator Working Principle Deaeration relies on the principle that the solubility of

neg: Common octopus diffuses into the blood. The tissues and muscles of the octopus use oxygen and release carbon dioxide when breaking down glucose in the Krebs cycle. The carbon dioxide then dissolves into the blood or combines with water to form carbonic acid which decreases blood pH. The Bohr Effect explains why oxygen concentrations are lower in venous blood than arterial blood and why oxygen diffuses into the blood stream. The rate of diffusion is affected by the distance the oxygen has to travel from the water to the blood stream as indicated by Fick's laws of diffusion. Fick's laws explain why

neg: Chloroplast species, recent results in tobacco plants are promising, showing a failed containment rate of transplastomic plants at 3 in 1,000,000. 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

neg: Leaf some foliose lichens, which are not plants at all (in the sense of being members of the kingdom Plantae), look and function much like leaves. Leaves are the most important organs of most vascular plants. Green plants are autotrophic, meaning that they do not obtain food from other living things but instead create their own by photosynthesis. They capture the energy in sunlight and use it to make simple sugars, such as glucose and sucrose, from carbon dioxide and water. The sugars are then stored as starch, further processed by chemical synthesis into more complex organic molecules such as proteins

neg: Evolution of photosynthesis sunlight into electric power using a pigment called xanthopterin. This is the first scientific evidence of a member of the animal kingdom engaging in photosynthesis. Photosynthesis is not quite as simple as adding water to to produce sugars and oxygen. A complex chemical pathway is involved, facilitated along the way by a range of enzymes and co-enzymes. The enzyme RuBisCO is responsible for "fixing" – that is, it attaches it to a carbon-based molecule to form a sugar, which can be used by the plant, releasing an oxygen molecule along the way. However, the enzyme is notoriously inefficient, and just

neg: Estuarine acidification pH on a daily, seasonal, and annual basis. During photosynthesis, carbon dioxide is removed from the water, increasing pH. Organisms release carbon dioxide during respiration. This leads to a daily cycle of increased pH during daylight hours and a decrease in pH during the night, when respiration is dominant. Similarly, pH is higher during the winter when grazing is low compared to productivity. Many estuaries experience nutrient loading from runoff containing wastewater effluent or fertilizers, natural or artificial. Increased nutrients can stimulate primary productivity and alter the balance between primary productivity and respiration. This process can change pH by whole

neg: Carbon dioxide in Earth's atmosphere energy needed for this reaction from absorption of sunlight by chlorophyll and other pigments. Oxygen, produced as a by-product of photosynthesis, is released into the atmosphere and subsequently used for respiration by heterotrophic organisms and other plants, forming a cycle. Most sources of emissions are natural, and are balanced to various degrees by natural sinks. For example, the natural decay of organic material in forests and grasslands and the action of forest fires results in the release of about 439 gigatonnes of carbon dioxide every year, while new growth entirely counteracts this effect, absorbing 450 gigatonnes per year. Although the

neg: Speleogenesis Speleogenesis Speleogenesis is the origin and development of caves, the primary process that determines essential features of the hydrogeology of karst and guides its evolution. It often deals with the development of caves through limestone, caused by the presence of water with carbon dioxide dissolved within it, producing carbonic acid which permits the dissociation of the calcium carbonate in the limestone. The majority of limestone caves are created by calcium carbonate dissolution by the solvent action of meteoric waters circulating through the rock. In the presence of carbon dioxide saturated water, calcium carbonate reacts to form the soluble calcium bicarbonate.