the main product of photosynthesis used by plants is
carbohydrate molecules
331476
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
Photosynthesis
331476
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
Photosynthesis
331537
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,
Photosynthesis
49612
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
Botany
331498
the newly formed NADPH and releases three-carbon sugars, which are later combined to form sucrose and starch. The overall equation for the light-independent reactions in green plants is Carbon fixation produces the intermediate three-carbon sugar product, which is then converted into the final carbohydrate products. The simple carbon sugars produced by photosynthesis are then used in the forming of other organic compounds, such as the building material cellulose, the precursors for lipid and amino acid biosynthesis, or as a fuel in cellular respiration. The latter occurs not only in plants but also in animals when the energy from plants is
Photosynthesis
331533
At 1000 ppm CO in measuring air, both the C3 and C4 plants had similar leaf photosynthetic rates around 60 μmol CO·m·s indicating the suppression of photorespiration in C3 plants. There are three main factors affecting photosynthesis and several corollary factors. The three main are: Total photosynthesis is limited by a range of environmental factors. These include the amount of light available, the amount of leaf area a plant has to capture light (shading by other plants is a major limitation of photosynthesis), rate at which carbon dioxide can be supplied to the chloroplasts to support photosynthesis, the availability of
Photosynthesis
2711314
Photorespiration Photorespiration (also known as the oxidative photosynthetic carbon cycle, or C photosynthesis) refers to a process in plant metabolism where the enzyme RuBisCO oxygenates RuBP, causing some of the energy produced by photosynthesis to be wasted. The desired reaction is the addition of carbon dioxide to RuBP (carboxylation), a key step in the Calvin–Benson cycle, however approximately 25% of reactions by RuBisCO instead add oxygen to RuBP (oxygenation), creating a product that cannot be used within the Calvin–Benson cycle. This process reduces the efficiency of photosynthesis, potentially reducing photosynthetic output by 25% in plants. Photorespiration involves a complex network
Photorespiration
9264397
can be used by crewmembers can be achieved by two means: physiochemically or biologically. Physiochemical processes such as the Sabatier reaction would result in high efficiencies however a large amount of energy is required in terms of temperature and pressure. Whereas biologically, using photosynthesis, efficiencies are lower, however ambient temperatures and pressures can be used. Photosynthesis is the process whereby plants convert light energy into chemical energy of sugars and other organic compounds. The chemical reactions utilise carbon and water with the by-product of oxygen, released into the atmosphere. MELiSSA is partly based on these photosynthetic reactions: recycling carbon dioxide
MELiSSA
278170
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 enzyme RuBisCO as part of the Calvin – Benson cycle. Three types of photosynthesis occur in plants, C3 carbon fixation, C4 carbon fixation and CAM photosynthesis. These differ by the route that carbon dioxide takes to the Calvin cycle, with C3 plants fixing CO directly, while C4 and CAM photosynthesis incorporate the CO into other compounds first, as adaptations
Metabolism
10984380
Sulfentrazone Sulfentrazone is a chemical used as a herbicide. It is the active ingredient in Dismiss as well as Solitare herbicides. It controls weeds by disrupting membranes and inhibits photosynthesis in plants commonly known as PPO Inhibition. Sulfentrazone is received in the plants through the roots of the plants. As the plants come out of the soil , they die after exposure to light. It also works of foliar contact causing rapid desiccation. Sulfentrazone kills annual and perennial sedges, cool season grasses(Poa annua, Poa trivialis) The labels on Sulfentrazone product from Ortho indicate use on Well established turf grasses. Cool
Sulfentrazone
331490
that leads to the ultimate reduction of NADP to NADPH. In addition, this creates a proton gradient (energy gradient) across the chloroplast membrane, which is used by ATP synthase in the synthesis of ATP. The chlorophyll molecule ultimately regains the electron it lost when a water molecule is split in a process called photolysis, which releases a dioxygen (O) molecule as a waste product. The overall equation for the light-dependent reactions under the conditions of non-cyclic electron flow in green plants is: Not all wavelengths of light can support photosynthesis. The photosynthetic action spectrum depends on the type of accessory
Photosynthesis
1876385
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
Excretion
20655041
product 3-phosphoglycerate is depleted in C due to the kinetic isotope effect of the above reaction. The overall C fractionation for C3 photosynthesis ranges between -20 to -37‰. The wide range of variation in delta values expressed in C3 plants is modulated by the stomatal conductance, or the rate of CO entering, or water vapor exiting, the small pores in the epidermis of a leaf. The δC of C3 plants depends on the relationship between stomatal conductance and photosynthetic rate, which is a good proxy of water use efficiency in the leaf. C3 plants with high water-use efficiency tend to
Fractionation of carbon isotopes in oxygenic photosynthesis
2518870
cycle, a coupled and self-recovering enzyme system, which is used to build branched carbohydrates. The by-product pyruvate can be further degraded in the mitochondrial citric acid cycle, thereby providing additional molecules for the Calvin Cycle. Pyruvate can also be used to recover PEP via pyruvate phosphate dikinase, a high-energy step, which requires ATP and an additional phosphate. During the following cool night, PEP is finally exported into the cytoplasm, where it is involved in fixing carbon dioxide via malate. Plants use CAM to different degrees. Some are "obligate CAM plants", i.e. they use only CAM in photosynthesis, although they vary
Crassulacean acid metabolism
167840
a product of photosynthesis. Glucose is also formed by the breakdown of polymeric forms of glucose like glycogen (in animals and mushrooms) or starch (in plants). The cleavage of glycogen is termed glycogenolysis, the cleavage of starch is called starch degradation. The metabolic pathway that begins with molecules containing two to four carbon atoms (C) and ends in the glucose molecule containing six carbon atoms is called gluconeogenesis and occurs in all living organisms. The smaller starting materials are the result of other metabolic pathways. Ultimately almost all biomolecules come from the assimilation of carbon dioxide in plants during photosynthesis.
Glucose
331481
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
Photosynthesis
877548
diffusion, and contains carbon dioxide and oxygen, which are used in photosynthesis and respiration, respectively. Oxygen produced as a by-product of photosynthesis diffuses out to the atmosphere through these same openings. Also, water vapor diffuses through the stomata into the atmosphere in a process called transpiration. Stomata are present in the sporophyte generation of all land plant groups except liverworts. In vascular plants the number, size and distribution of stomata varies widely. Dicotyledons usually have more stomata on the lower surface of the leaves than the upper surface. Monocotyledons such as onion, oat and maize may have about the same
Stoma
7145815
net 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 intensity. This dramatically reduces average achieved photosynthetic efficiency in fields compared to peak laboratory results. However, real plants (as opposed to laboratory
Photosynthetic efficiency
7426074
excreta. Some mammals including humans excrete uric acid as a component of their urine but it is only a small amount. These compounds form during the catabolism of carbohydrates and lipids in condensation reactions, and in some other metabolic reactions of the amino acids. Oxygen is produced by plants and some bacteria in photosynthesis, while CO is a waste product of all animals and plants. Nitrogen gases are produced by denitrifying bacteria and as a waste product, and bacteria for decaying yield ammonia, as do most invertebrates and vertebrates. Water is the only liquid waste from animals and photosynthesizing plants.
Metabolic waste
17569653
a free-living state in naturally occurring bacterial communities. "C. chlorochromatii" conducts anoxygenic photosynthesis which means it does not produce oxygen as a waste product like plants and cyanobacteria, this type of photosynthesis is exclusive to Bacteria. In their electron transport chain reduced forms of sulfur, e.g., HS. These reduced forms of sulfur are used in the electron transport chain cyclic Photosystem 1 as electron donors to reduce NADP+ to NADPH. It grows under strictly anaerobic conditions as a photolithoautotroph. They grow best at a pH of 7.0-7.3 at 25 C in continuous light and absorb light maximally at 748 and
Chlorobium chlorochromatii
1639917
for respiration; nitrogen is fixed by bacteria and lightning to produce ammonia used in the construction of nucleotides and amino acids; and carbon dioxide is used by plants, algae and cyanobacteria for photosynthesis. The atmosphere helps to protect living organisms from genetic damage by solar ultraviolet radiation, solar wind and cosmic rays. The current composition of the Earth's atmosphere is the product of billions of years of biochemical modification of the paleoatmosphere by living organisms. The term stellar atmosphere describes the outer region of a star and typically includes the portion above the opaque photosphere. Stars with sufficiently low temperatures
Atmosphere
12607082
are able to persist in drought better than the C3 plants. Increases in temperature raise the rate of many physiological processes such as photosynthesis in plants, to an upper limit, depending on the type of plant. These increases in photosynthesis and other physiological processes are driven by increased rates of chemical reactions and roughly a doubling of enzymatic product conversion rates for every 10 °C increase in temperature. Extreme temperatures can be harmful when beyond the physiological limits of a plant which will eventually lead to higher desiccation rates. One common hypothesis among scientists is that the warmer an area
Effects of climate change on plant biodiversity
17743293
toxicity to animals with no restrictions on swimming or drinking in treated water bodies. Fluridone breaks down in the environment over days or weeks with the major degradation product being N-methyl formamide. The half-life of fluridone in soils and sediments is nine months. Fluridone is a systemic herbicide that works by interfering with carotene formation which leads to chlorophyll degradation. Fluridone and are inhibitors of chloroplastic and cyanobacterial Phytoene desaturase, which in turn disrupts the carotenoid biosynthetic pathway. Fluridone's main action to disrupt photosynthesis in plants is by preventing the secretion of abscisic acid. As higher eukaryotes, such as humans,
Fluridone
17758108
Evolution of photosynthesis The evolution of photosynthesis refers to the origin and subsequent evolution of photosynthesis, the process by which light energy synthesizes sugars from carbon dioxide, releasing oxygen as a waste product. The process of photosynthesis was discovered by Jan Ingenhousz, a Dutch-born British physician and scientist, first publishing about it in 1779. The first photosynthetic organisms probably evolved early in the evolutionary history of life and most likely used reducing agents such as hydrogen or electrons, rather than water. There are three major metabolic pathways by which photosynthesis is carried out: C photosynthesis, C photosynthesis, and CAM photosynthesis.
Evolution of photosynthesis
331514
More recent studies, reported in March 2018, also suggest that photosynthesis may have begun about 3.4 billion years ago. The main source of oxygen in the Earth's atmosphere derives from oxygenic photosynthesis, and its first appearance is sometimes referred to as the oxygen catastrophe. Geological evidence suggests that oxygenic photosynthesis, such as that in cyanobacteria, became important during the Paleoproterozoic era around 2 billion years ago. Modern photosynthesis in plants and most photosynthetic prokaryotes is oxygenic. Oxygenic photosynthesis uses water as an electron donor, which is oxidized to molecular oxygen () in the photosynthetic reaction center. Several groups of animals
Photosynthesis
17318540
nine enzymatic reactions, ultimately resulting in the synthesis of vitamin K. This pathway is quite similar in both plants and bacteria, however the final product of the pathway varies slightly in the two organisms. The final product in plants and some cyanobacteria is phylloquinone, which functions as an electron transporter in photosynthesis. The final product in bacteria and archaea is menaquinone, which is involved in anaerobic respiration. The structures of the two end-products are illustrated below. Phylloquinone is commonly called "vitamin K." Menaquinone is commonly called "vitamin K." Both fall under the common name "vitamin K." This pathway is not
O-succinylbenzoate synthase
14111678
why it climbs high in the canopy. "R. cissoides" requires essential plant macronutrients. There are many nutrients which plants require to maintain good growth but the main three are nitrogen, phosphorus and potassium (NPK). Out of these three macronutrients nitrogen is the most important for plant growth. Nitrogen is essential for the process of photosynthesis to occur. Photosynthesis produces energy for plant. "R. cissoides" will need a wide range of nutrients in the soil to remain healthy, especially NPK. The hooks on "R. cissoides" are mainly used for assisting with climbing, but also assist the plant in terms of protection
Rubus cissoides
11741286
water, and light for the survival of plants that are housed in it, as well as a reservoir of water, as water is trapped inside the bottle and unable to evaporate. The carbon dioxide from plant respiration is used for photosynthesis, and the oxygen from photosynthesis is used for respiration. As such they require almost no maintenance. Bottle garden A bottle garden is a container similar to a terrarium in which plants are grown. They usually consist of a plastic or glass bottle with a narrow neck and a small opening. Plants are grown inside the bottle with little or
Bottle garden
15335621
is the lack of an effective way to remove these pollutants on a large scale expediently. In nature, organisms "recycle" the wastes of other organisms, for example, plants produce oxygen as a by-product of photosynthesis, oxygen-breathing organisms use oxygen to metabolize food, producing carbon dioxide as a by-product, which plants use in a process to make sugar, with oxygen as a waste in the first place. No such mechanism exists for the removal of technological wastes. Society also controls technology through the choices it makes. These choices not only include consumer demands; they also include: According to Williams and Edge,
Technology and society
13994704
can only use a fraction of this energy for photosynthesis, approximately 1% is used by autotrophs. The process of photosynthesis splits a water molecule (HO), releasing oxygen (O) into the atmosphere, and reducing carbon dioxide (CO) to release the hydrogen atoms that fuel the metabolic process of primary production. Plants convert and store the energy of the photon into the chemical bonds of simple sugars during photosynthesis. These plant sugars are polymerized for storage as long-chain carbohydrates, including other sugars, starch, and cellulose; glucose is also used to make fats and proteins. When autotrophs are eaten by heterotrophs, i.e., consumers
Autotroph
2875118
cytochrome "c" One of the main reasons for interest in "Chloroflexus aurantiacus" is in the study of the evolution of photosynthesis. As terrestrial mammals, we are most familiar with photosynthetic plants such as trees. However, photosynthetic eukaryotes are a relatively recent evolutionary development. Photosynthesis by eukaryotic organisms can be traced back to endosymbiotic events in which non-photosynthetic eukaryotes internalized photosynthetic organisms. The chloroplasts of trees still retain their own DNA as a molecular remnant that indicated their origin as photosynthetic bacteria. How did photosynthesis arise in bacteria? The answer to this question is complicated by the fact that there are
Chloroflexus aurantiacus
331491
pigments present. For example, in green plants, the action spectrum resembles the absorption spectrum for chlorophylls and carotenoids with absorption peaks in violet-blue and red light. In red algae, the action spectrum is blue-green light, which allows these algae to use the blue end of the spectrum to grow in the deeper waters that filter out the longer wavelengths (red light) used by above ground green plants. The non-absorbed part of the light spectrum is what gives photosynthetic organisms their color (e.g., green plants, red algae, purple bacteria) and is the least effective for photosynthesis in the respective organisms. In
Photosynthesis
10238239
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
Carbon dioxide in Earth's atmosphere
4489796
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% for C3 and C4 plants respectively. In reality, the efficiency of photosynthesis is much lower and is usually below 1%, with some exceptions such as sugarcane in tropical climate. In contrast, the highest reported efficiency for artificial photosynthesis lab prototypes is 22.4%. However, plants are efficient in using CO at atmospheric
Artificial photosynthesis
4489760
energy conversion efficiency (due to photosynthesis' own low efficiency in converting sunlight to biomass), the cost of harvesting and transporting the fuel, and conflicts due to the increasing need of land mass for food production. The purpose of artificial photosynthesis is to produce a fuel from sunlight that can be stored conveniently and used when sunlight is not available, by using direct processes, that is, to produce a solar fuel. With the development of catalysts able to reproduce the major parts of photosynthesis, water and sunlight would ultimately be the only needed sources for clean energy production. The only by-product
Artificial photosynthesis
12366088
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
Xerophyte
20655031
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
Fractionation of carbon isotopes in oxygenic photosynthesis
73078
also be altered in plants exposed to high concentrations of . Plants also emit during respiration, and so the majority of plants and algae, which use C3 photosynthesis, are only net absorbers during the day. Though a growing forest will absorb many tons of each year, a mature forest will produce as much from respiration and decomposition of dead specimens (e.g., fallen branches) as is used in photosynthesis in growing plants. Contrary to the long-standing view that they are carbon neutral, mature forests can continue to accumulate carbon and remain valuable carbon sinks, helping to maintain the carbon balance of
Carbon dioxide
5616777
express in the host organism. Transgenic plants are used to express proteins like the cry toxins from "B. thuringiensis", herbicide resistant genes, antibodies and antigens for vaccinations A study led by the European Food Safety Authority (EFSA) found also viral genes in transgenic plants. Transgenic carrots have been used to produce the drug Taliglucerase alfa which is used to treat Gaucher's disease. In the laboratory, transgenic plants have been modified to increase photosynthesis (currently about 2% at most plants versus the theoretic potential of 9–10%). This is possible by changing the rubisco enzyme (i.e. changing C3 plants into C4 plants),
Genetically modified crops
11232514
indicated by the detection of 6 phenotypes within a small European population. Phosphoglycolate phosphatase Phosphoglycolate phosphatase(PGP), also commonly referred to as phosphoglycolate hydrolase, 2-phosphoglycolate phosphatase, P-glycolate phosphatase, and phosphoglycollate phosphatase, is an enzyme responsible for catalyzing the conversion of 2-phosphoglycolate into glycolate and phosphate. First studied and purified within plants, phosphoglycolate phosphatase plays a major role in photorespiratory 2-phosphoglycolate metabolism, an essential pathway for photosynthesis in plants. The occurrence of photorespiration in plants, due to the lack of substrate specificity of rubisco, leads to the formation of 2-phosphoglycolate and 3-phosphogylcerate(PGA). PGA is the normal product of carboxylation and will enter
Phosphoglycolate phosphatase
6357519
Products of photosynthesis are used up in respiration so that the organism is neither consuming nor building biomass. The net gaseous exchange is also zero at this point. For aquatic plants where the level of light at any given depth is roughly constant for most of the day, the compensation point is the depth at which light penetrating the water creates the same balanced effect. Respiration occurs by both plants and animals throughout the water column, resulting in the destruction, or usage, of organic matter, but photosynthesis can only take place via photosynthetic algae in the presence of light, nutrients
Compensation point
610481
many food plants along with the monosaccharide fructose. In many fruits, such as pineapple and apricot, sucrose is the main sugar. In others, such as grapes and pears, fructose is the main sugar. Although sucrose is almost invariably isolated from natural sources, its chemical synthesis was first achieved in 1953 by Raymond Lemieux. In nature, sucrose is present in many plants, and in particular their roots, fruits and nectars, because it serves as a way to store energy, primarily from photosynthesis. Many mammals, birds, insects and bacteria accumulate and feed on the sucrose in plants and for some it is
Sucrose
49622
to produce molecules of the 3-carbon sugar glyceraldehyde 3-phosphate (G3P). Glyceraldehyde 3-phosphate is the first product of photosynthesis and the raw material from which glucose and almost all other organic molecules of biological origin are synthesised. Some of the glucose is converted to starch which is stored in the chloroplast. Starch is the characteristic energy store of most land plants and algae, while inulin, a polymer of fructose is used for the same purpose in the sunflower family Asteraceae. Some of the glucose is converted to sucrose (common table sugar) for export to the rest of the plant. Unlike in
Botany
49650
oxygenic photosynthesis and released by cellular respiration, is the basis of almost all life. Photoautotrophs, including all green plants, algae and cyanobacteria gather energy directly from sunlight by photosynthesis. Heterotrophs including all animals, all fungi, all completely parasitic plants, and non-photosynthetic bacteria take in organic molecules produced by photoautotrophs and respire them or use them in the construction of cells and tissues. Respiration is the oxidation of carbon compounds by breaking them down into simpler structures to release the energy they contain, essentially the opposite of photosynthesis. Molecules are moved within plants by transport processes that operate at a variety
Botany
99256
days. Although in most cacti, the stem acts as the main organ for storing water, some cacti have in addition large taproots. These may be several times the length of the above-ground body in the case of species such as "Copiapoa atacamensis", which grows in one of the driest places in the world, the Atacama Desert in northern Chile. Photosynthesis requires plants to take in carbon dioxide gas (). As they do so, they lose water through transpiration. Like other types of succulents, cacti reduce this water loss by the way in which they carry out photosynthesis. "Normal" leafy plants
Cactus
7397450
photosynthesis. This is also a main way that primary producers take energy and produce/release it somewhere else. Plants, coral, bacteria, and algae do this. Bacteria is a more recent find in the process of photosynthesis with primary producers, as they were just discovered in the soil. During photosynthesis, primary producers take energy from the sun and produce it into energy, sugar, and oxygen. Primary producers also need energy to convert this same energy elsewhere, so they get it from nutrients. One type of nutrient is nitrogen. Without primary producers, organisms that are capable of producing energy on their own, the
Primary producers
3257116
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, and use the Calvin cycle to fix carbon autotrophically. The process works like this: In the first step, water is dissociated into electrons, protons, and free oxygen. This allows the use of water, one of the most abundant substances on Earth, as
Carbon fixation
6089296
primarily on photosynthesis. The total energy captured by photosynthesis in green plants from the solar radiation is about 2 x 10 joules of energy per year. Annual energy captured by photosynthesis in green plants is about 4% of the total sunlight energy that reaches Earth. The energy transformations in biological communities surrounding hydrothermal vents are exceptions; they oxidize sulfur, obtaining their energy via chemosynthesis rather than photosynthesis. The field of biological thermodynamics is focused on principles of chemical thermodynamics in biology and biochemistry. Principles covered include the first law of thermodynamics, the second law of thermodynamics, Gibbs free energy, statistical
Biological thermodynamics
5166778
98.9 to 1.1. The C and C ratio is either depleted (more negative) or enriched (more positive) relative to the international standard, which is set to an arbitrary zero. The different photosynthesis pathways used by C3 and C4 plants cause them to discriminate differently towards C The C4 and C3 plants have distinctly different ranges of C; C4 plants range between -9 and -16 per mil, and C3 plants range between -22 to -34 per mil. δC studies have been used in North America to document the transition from a C3 to a C4 (native North American plants to corn)
Bioarchaeology
11232501
Phosphoglycolate phosphatase Phosphoglycolate phosphatase(PGP), also commonly referred to as phosphoglycolate hydrolase, 2-phosphoglycolate phosphatase, P-glycolate phosphatase, and phosphoglycollate phosphatase, is an enzyme responsible for catalyzing the conversion of 2-phosphoglycolate into glycolate and phosphate. First studied and purified within plants, phosphoglycolate phosphatase plays a major role in photorespiratory 2-phosphoglycolate metabolism, an essential pathway for photosynthesis in plants. The occurrence of photorespiration in plants, due to the lack of substrate specificity of rubisco, leads to the formation of 2-phosphoglycolate and 3-phosphogylcerate(PGA). PGA is the normal product of carboxylation and will enter the Calvin cycle. Phosphoglycolate, which is a potent inhibitor of phosphofructokinase and
Phosphoglycolate phosphatase
12366449
photosynthesis, the total gross gain of biomass by photosynthesis, minus the biomass lost by respiration. Understanding carnivory requires a cost-benefit analysis of these factors. In carnivorous plants, the leaf is not just used to photosynthesise, but also as a trap. Changing the leaf shape to make it a better trap generally makes it less efficient at photosynthesis. For example, pitchers have to be held upright, so that only their opercula directly intercept light. The plant also has to expend extra energy on non-photosynthetic structures like glands, hairs, glue and digestive enzymes. To produce such structures, the plant requires ATP and
Carnivorous plant
2518877
distribution of plants with CAM: Crassulacean acid metabolism Crassulacean acid metabolism, also known as CAM photosynthesis, is a carbon fixation pathway that evolved in some plants as an adaptation to arid conditions. In a plant using full CAM, the stomata in the leaves remain shut during the day to reduce evapotranspiration, but open at night to collect carbon dioxide (). The is stored as the four-carbon acid malate in vacuoles at night, and then in the daytime, the malate is transported to chloroplasts where it is converted back to , which is then used during photosynthesis. The pre-collected is concentrated
Crassulacean acid metabolism
13691848
removed from an excited chlorophyll molecule and used to reduce NAD to NADH. The electrons removed from P840 must be replaced. This is accomplished by removing electrons from , which is oxidized to sulfur (hence the name "green "sulfur" bacteria"). Purple bacteria and green sulfur bacteria occupy relatively minor ecological niches in the present day biosphere. They are of interest because of their importance in precambrian ecologies, and because their methods of photosynthesis were the likely evolutionary precursors of those in modern plants. The first ideas about light being used in photosynthesis were proposed by Colin Flannery in 1779 who
Light-dependent reactions
20655042
be less fractionated in C (ie, δC is relatively less negative) compared to C3 plants with low water-use efficiency. C4 plants have developed the C4 carbon fixation pathway to conserve water loss, thus are more prevalent in hot, sunny, and dry climates. These plants differ from C3 plants because the Calvin Cycle in C4 plants produces a four-carbon molecule, malate (rather than 3-phosphoglycerate), after fixation of CO. Malate, the four-carbon compound is the namesake of "C4" photosynthesis. This pathway allows C4 photosynthesis to efficiently shuttle CO to the RuBisCO enzyme and maintain high concentrations of CO within bundle sheath cells.
Fractionation of carbon isotopes in oxygenic photosynthesis
4021383
its environment. The main carbon source (carbon dioxide) needs to be solubilized in the apoplast before it diffuses through the plasma membrane into the cell's cytoplasm (symplast) and is used by the chloroplasts during photosynthesis. In the roots, ions diffuse into the apoplast of the epidermis before diffusing into the symplast, or in some cases being taken up by specific ion channels, and being pulled by the plant's transpiration stream, which also occurs completely within the boundaries of the apoplast. Similarly, all gaseous molecules emitted and received by plants such as plant hormones and other pheromones must pass the apoplast.
Apoplast
12366090
Thus, the seed and plant can utilise the water available from short-lived rainfall for a much longer time compared to mesophytic plants. During dry times, resurrection plants look dead, but are actually alive. Some xerophytic plants may stop growing and go dormant, or change the allocation of the products of photosynthesis from growing new leaves to the roots. These plants evolved to be able to coordinately switch off their photosynthetic mechanism without destroying the molecules involved in photosynthesis. When water is available again, these plants would "resurrect from the dead" and resume photosynthesis, even after they had lost more than
Xerophyte
12465131
to its first singlet excited state. The excited state then has three main fates. Either the energy is; 1. passed to another chlorophyll molecule by Förster resonance energy transfer (in this way excitation is gradually passed to the photochemical reaction centers (photosystem I and photosystem II) where energy is used in photosynthesis (called photochemical quenching); or 2. the excited state can return to the ground state by emitting the energy as heat (called non-photochemical quenching); or 3. the excited state can return to the ground state by emitting a photon (fluorescence). In higher plants, the absorption of light continues to
Non-photochemical quenching
4153276
for. General structural classes of secondary metabolites include alkaloids, phenylpropanoids, polyketides, and terpenoids, which are described in more detail in the biosynthesis section below. The biosynthetic pathways leading to the major classes of natural products are described below. Carbohydrates are an essential energy source for most life forms. In addition, polysaccharides formed from simpler carbohydrates are important structural components of many organisms such the cell walls of bacteria and plants. Carbohydrate are the products of plant photosynthesis and animal gluconeogenesis. Photosynthesis produces initially 3-phosphoglyceraldehyde, a three carbon atom containing sugar (a triose). This triose in turn may be converted into
Natural product
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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
Carbon dioxide in Earth's atmosphere
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Antheraxanthin Antheraxanthin (from "ánthos", Greek for "flower" and "xanthos", Greek for "yellow") is a bright yellow accessory pigment found in many organisms that perform photosynthesis. It is a xanthophyll cycle pigment, an oil-soluble alcohol within the xanthophyll subgroup of carotenoids. Antheraxanthin is both a component in and product of the cellular photoprotection mechanisms in photosynthetic green algae, red algae, euglenoids, and plants. Antheraxanthin is an intermediate molecule of the xanthophyll cycle in most photosynthetic eukaryotes, namely plants, and some bacteria. In the xanthophyll cycle, specific carotenoid pigments are transformed via enzymatic reactions into either more or less photoprotective biological pigments.
Antheraxanthin
331500
thus "recycled" often condense to form hexose phosphates, which ultimately yield sucrose, starch and cellulose. The sugars produced during carbon metabolism yield carbon skeletons that can be used for other metabolic reactions like the production of amino acids and lipids. In hot and dry conditions, plants close their stomata to prevent water loss. Under these conditions, will decrease and oxygen gas, produced by the light reactions of photosynthesis, will increase, causing an increase of photorespiration by the oxygenase activity of ribulose-1,5-bisphosphate carboxylase/oxygenase and decrease in carbon fixation. Some plants have evolved mechanisms to increase the concentration in the leaves under
Photosynthesis
126404
energy flows in physical and biological systems by expressing energy units in human terms: it provides a "feel" for the use of a given amount of energy. Sunlight's radiant energy is also captured by plants as "chemical potential energy" in photosynthesis, when carbon dioxide and water (two low-energy compounds) are converted into the high-energy compounds carbohydrates, lipids, and proteins. Plants also release oxygen during photosynthesis, which is utilized by living organisms as an electron acceptor, to release the energy of carbohydrates, lipids, and proteins. Release of the energy stored during photosynthesis as heat or light may be triggered suddenly by
Energy
4011718
interchange of water molecules in S-states. The arrangement of hydrogen bonding is main criteria of the diagrams. The effect of photon(hv), emission of electron(e) and production of hydrogen ion(H+) from water molecules can be shown by the diagrams in a more specific way of experimental detection. The diagrams almost completely analyze the pathway of water-splitting in photosynthesis. Photosystem II Photosystem II (or water-plastoquinone oxidoreductase) is the first protein complex in the light-dependent reactions of oxygenic photosynthesis. It is located in the thylakoid membrane of plants, algae, and cyanobacteria. Within the photosystem, enzymes capture photons of light to energize electrons that
Photosystem II
73074
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
Carbon dioxide
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Urbana-Champaign, and then on Photosystem II in 1989 with Michael Wasielewski at Argonne National Laboratory. He is best known for establishing the unique role of bicarbonate in electron and proton transport in Photosystem II. Govindjee has not only provided the first comprehensive theory of thermoluminescence in algae and plants, but has shown how prompt and delayed fluorescence of Chlorophyll a can be used as a signature of various reactions in photosynthesis. He is the founding Series Editor of the "Advances in Photosynthesis and Respiration" as well as the Editor of "Historical Corner" of "Photosynthesis Research". He has written extensively on
Govindjee
376261
run through adjacent fuel-cell electric power plants and the pure water by-product going directly into the municipal water system. Another vision involves all human structures covering the earth's surface (i.e., roads, vehicles and buildings) doing photosynthesis more efficiently than plants. Hydrogen production technologies have been a significant area of solar chemical research since the 1970s. Aside from electrolysis driven by photovoltaic or photochemical cells, several thermochemical processes have also been explored. One such route uses concentrators to split water into oxygen and hydrogen at high temperatures (). Another approach uses the heat from solar concentrators to drive the steam reformation
Solar energy
17758119
in an environment with much more than it otherwise would be, it performs more efficiently. A second mechanism, CAM photosynthesis, is a carbon fixation pathway that evolved in some plants as an adaptation to arid conditions. The most important benefit of CAM to the plant is the ability to leave most leaf stomata closed during the day. This reduces water loss due to evapotranspiration. The stomata open at night to collect , which is stored as the four-carbon acid malate, and then used during photosynthesis during the day. The pre-collected is concentrated around the enzyme RuBisCO, increasing photosynthetic efficiency. More
Evolution of photosynthesis
20855587
can transfer various infochemicals is that they have been show to transfer molecules such as lipids, carbohydrates and amino acids. Thus, transfer of infochemicals via mycorrhizal networks can act to influence plant behavior. There are three main types of infochemicals shown to act as response inducing signals or cues by plants in mycorrhizal networks, as evidenced by increased effects on plant behavior: allelochemicals, defensive chemicals and nutrients. Allelopathy is the process by which plants produce secondary metabolites known as allelochemicals, which can interfere with the development of other plants or organisms. Allelochemicals can affect nutrient uptake, photosynthesis and growth; furthermore,
Plant to plant communication via mycorrhizal networks
331477
Earth's atmosphere, and supplies all of the organic compounds and most of the energy necessary for life on Earth. Although photosynthesis is performed differently by different species, the process always begins when energy from light is absorbed by proteins called reaction centres that contain green chlorophyll pigments. In plants, these proteins are held inside organelles called chloroplasts, which are most abundant in leaf cells, while in bacteria they are embedded in the plasma membrane. In these light-dependent reactions, some energy is used to strip electrons from suitable substances, such as water, producing oxygen gas. The hydrogen freed by the splitting
Photosynthesis
20655048
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
Fractionation of carbon isotopes in oxygenic photosynthesis
19148233
of water provides the electrons needed by the antenna system of photosystem II where they are boosted in energy and then sent along the electron transport system (ETS). Those high energy electrons are able to move against a chemical potential gradient. Hence, solar energy is converted to chemical energy by the reduction of NADP to NADPH. Photosynthesis is the process in which light energy is absorbed and converted to chemical energy. This chemical energy is eventually used in the conversion of carbon dioxide (CO) to sugar (CHO) in plants. During the process of photosynthesis, a natural electron acceptor, nicotinamide adenine
Hill reaction
19842428
Thomas D. Sharkey Thomas D. Sharkey is a plant biochemist who studies gas exchange between plants and the atmosphere. His research has covered (1) carbon metabolism of photosynthesis from carbon dioxide uptake to carbon export from the Calvin-Benson Cycle, (2) isoprene emission from plants, and (3) abiotic stress tolerance. Four guiding questions are: (1) how leaf photosynthesis affects plant yield, (2) does some carbon fixation follow an oxidative pathway that reduces sugar output but stabilizes photosynthesis, (3) why plants make isoprene, and (4) how plants cope with high temperature. Tom Sharkey obtained a BS degree in 1974 from Lyman Briggs
Thomas D. Sharkey
7188293
allows us to measure the oxygen uptake by the photorespiration pathway. Labeling by gives the unidirectional flux of uptake, while there is a net photosynthetic evolution. It was demonstrated that, under preindustrial atmosphere, most plants reabsorb, by photorespiration, half of the oxygen produced by photosynthesis. Then, the yield of photosynthesis was halved by the presence of oxygen in atmosphere. Fluorine-18 is usually produced by irradiation of O-enriched water (HO) with high-energy (about 18 MeV) protons prepared in a cyclotron or a linear accelerator, yielding an aqueous solution of F fluoride. This solution is then used for rapid synthesis of a
Oxygen-18
7145823
than offset by the use of increased light. The ability to thrive despite restricted water availability maximizes the ability to use available light. The simpler C3 cycle which operates in most plants is adapted to wetter darker environments, such as many northern latitudes. . Corn, sugar cane, and sorghum are C4 plants. These plants are economically important in part because of their relatively high photosynthetic efficiencies compared to many other crops. Pineapple is a CAM plant. Photosynthetic efficiency The photosynthetic efficiency is the fraction of light energy converted into chemical energy during photosynthesis in plants and algae. Photosynthesis can be
Photosynthetic efficiency
17758112
as an electron donor. Green nonsulfur bacteria used various amino and other organic acids. Purple nonsulfur bacteria used a variety of nonspecific organic molecules. Fossils of what are thought to be filamentous photosynthetic organisms have been dated at 3.4 billion years old. More recent studies, reported in March 2018, also suggest that photosynthesis may have begun about 3.4 billion years ago. The main source of oxygen in the atmosphere is oxygenic photosynthesis, and its first appearance is sometimes referred to as the oxygen catastrophe. Geological evidence suggests that oxygenic photosynthesis, such as that in cyanobacteria, became important during the Paleoproterozoic
Evolution of photosynthesis
7145810
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 10 or more) photons to utilize one molecule of CO.
Photosynthetic efficiency
3085661
is included within the domain of plant physiology. To function and survive, plants produce a wide array of chemical compounds not found in other organisms. Photosynthesis requires a large array of pigments, enzymes, and other compounds to function. Because they cannot move, plants must also defend themselves chemically from herbivores, pathogens and competition from other plants. They do this by producing toxins and foul-tasting or smelling chemicals. Other compounds defend plants against disease, permit survival during drought, and prepare plants for dormancy, while other compounds are used to attract pollinators or herbivores to spread ripe seeds. Secondly, plant physiology includes
Plant physiology
7327398
This ability to photosynthesize atmospheric carbon dioxide to oxygen is characteristic of all plants that is the opposite process of cellular respiration, that all animals and non-photosynthetic organism rely on to sustain life. Both photosynthesis and cellular respiration are used to create energy that is used to carry out all functions in an organism. Since humans rely on cellular respiration, the conversion of oxygen to carbon dioxide, and algae relies on photosynthesis, the conversion of carbon dioxide to oxygen, astronauts were able to survive in space with a constant renewal of oxygen. This knowledge was not only beneficial to astronauts
Emmett Chappelle
15488366
to photosynthesis. They do this by transferring some of the light energy they absorb to chlorophylls, which then uses this energy for photosynthesis. Second, they can protect plants which are over-exposed to sunlight. They do this by harmlessly dissipating excess light energy which they absorb as heat. In the absence of carotenoids, this excess light energy could destroy proteins, membranes, and other molecules. Some plant physiologists believe that carotenoids may have an additional function as regulators of certain developmental responses in plants. Tetraterpenes are synthesized from DOXP precursors in plants and some bacteria. Carotenoids involved in photosynthesis are formed in
Plant secondary metabolism
6068329
before they start to defoliate, eventually they will die. Sometimes plants are able to refoliate and defoliate again during the growing season. Hexazinone Hexazinone is an organic compound that is used as a broad spectrum herbicide. It is a colorless solid. It exhibits some solubility in water but is highly soluble in most organic solvents except alkanes. A member of the triazine class herbicides, it is manufactured by DuPont and sold under the trade name Velpar. It functions by inhibiting photosynthesis and thus is a nonselective herbicide. It is used to control grasses, broadleaf, and woody plants. Approximately 33% is
Hexazinone
375899
tonnes of starch were being produced per year worldwide by 2008. In the EU this was around 8.5 million tonnes, with around 40% being used for industrial applications and 60% for food uses, most of the latter as glucose syrups. Most green plants use starch as their energy store.The extra glucose is changed into starch which is more complex than glucose(by plants). An exception is the family Asteraceae (asters, daisies and sunflowers), where starch is replaced by the fructan inulin. Inulin-like fructans are also present in grasses such as wheat, in onions and garlic, bananas, and asparagus. In photosynthesis, plants
Starch
20655051
values more similar to C3 plants. In contrast to terrestrial plants, where CO diffusion in air is relatively fast and typically not limiting, diffusion of dissolved CO in water is considerably slower and can often limit carbon fixation in phytoplankton. As gaseous CO is dissolved into aqueous CO, it is fractionated by both kinetic and equilibrium effects that are temperature-dependent. Relative to plants, the dissolved CO source for phytoplankton can be enriched in C by about 8‰ from atmospheric CO. Isotope fractionation of C by phytoplankton photosynthesis is affected by the diffusion of extracellular aqueous CO into the cell, the
Fractionation of carbon isotopes in oxygenic photosynthesis
20655049
the C3 pathway in the daytime and the C4 pathway in the nighttime. At night, when temperature and water loss are lower, the CO diffuses through the stomata and produce malate via phosphenolpyruvate carboxylase. During the following day, stomata are closed, malate is decarboxylated, and CO is fixed by RuBisCO. This process alone is similar to that of C4 plants and yields characteristic C4 fractionation values of approximately -11‰. However, in the afternoon, CAM plants may open their stomata and perform C3 photosynthesis. In daytime alone, CAM plants have approximately -28‰ fractionation, characteristic of C3 plants. These combined effects provide
Fractionation of carbon isotopes in oxygenic photosynthesis
376222
water cycle. The latent heat of water condensation amplifies convection, producing atmospheric phenomena such as wind, cyclones and anti-cyclones. Sunlight absorbed by the oceans and land masses keeps the surface at an average temperature of 14 °C. By photosynthesis, green plants convert solar energy into chemically stored energy, which produces food, wood and the biomass from which fossil fuels are derived. The total solar energy absorbed by Earth's atmosphere, oceans and land masses is approximately 3,850,000 exajoules (EJ) per year. In 2002, this was more energy in one hour than the world used in one year. Photosynthesis captures approximately 3,000
Solar energy
12366339
Plant stem A stem is one of two main structural axes of a vascular plant, the other being the root. The stem is normally divided into nodes and internodes: The term "shoots" is often confused with "stems"; "shoots" generally refers to new fresh plant growth including both stems and other structures like leaves or flowers. In most plants stems are located above the soil surface but some plants have underground stems. Stems have four main functions which are: Stems are often specialized for storage, asexual reproduction, protection or photosynthesis, including the following: Stem usually consist of three tissues, dermal tissue,
Plant stem
14765499
can exploit as a form of parasite control—e.g., through knock-out or inhibition of crucial transporters or destruction of penetrative anatomical features. Several studies have looked into nutrient acquisition as a method of parasite control, including the development of vaccines against helminth parasites by targeting digestive proteases. Plants are typically autotrophic organisms meaning that they synthesise their own 'food' from inorganic compounds by photosynthesis. Some plants however are unable to synthesise their own 'food' by photosynthesis and therefore acquire nutrients by parasitic nutrition from other living plants. Plants that acquire nutrients in this way are called "parasitic plants". These plants have
Parasitic nutrition
5489724
Fungiculture Fungiculture is the process of producing food, medicine, and other products by the cultivation of mushrooms and other fungi. A "mushroom farm" is in the business of growing fungi. The word is also commonly used to refer to the practice of cultivating fungi by leafcutter ants, termites, ambrosia beetles, and marsh periwinkles. Mushrooms 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,
Fungiculture
571584
secondary xylem is also found in members of the gymnosperm groups Gnetophyta and Ginkgophyta and to a lesser extent in members of the Cycadophyta, the two main groups in which secondary xylem can be found are: The xylem, vessels and tracheids of the roots, stems and leaves are interconnected to form a continuous system of water conducting channels reaching all parts of the plants. It transports water and soluble mineral nutrients from the roots throughout the plant. It is also used to replace water lost during transpiration and photosynthesis. Xylem sap consists mainly of water and inorganic ions, although it
Xylem
4679750
of silica produced by many plants such as grasses. Both pollen and phytolith fossils from different plant species have characteristic shapes that can be traced back to their parent plants. Over long geological time scales, phytoliths may not necessarily be preserved in paleosols due to ability of the poorly crystalline silica to dissolve. Another indicator of plant community composition in paleosols is the carbon isotopic signature. The ratio of different carbon isotopes in organic matter in paleosols reflects the proportions of plants using C3 photosynthesis, which grow in cooler and wetter climates, versus plants using C4 photosynthesis, which are better
Paleosol
12366089
examples of plants employing the CAM mechanism are the pineapple, "Agave Americana", and "Aeonium haworthii". Although some xerophytes perform photosynthesis using this mechanism, the majority of plants in arid regions still employ the C and C photosynthesis pathways. A small proportion of desert plants even use a collaborated C-CAM pathway. The surrounding humidity and moisture right before and during seed germination play an important role in the germination regulation in arid conditions. An evolutionary strategy employed by desert xerophytes is to reduce the rate of seed germination. By slowing the shoot growth, less water is consumed for growth and transpiration.
Xerophyte
11273911
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
Our Mr. Sun
12323870
and air are trapped between the ice crystals. Nilas may have a salinity of 12–15 ‰, but by the time the sea ice is one year old, this falls to 4–6 ‰. The amount of oxygen found in seawater depends primarily on the plants growing in it. These are mainly algae, including phytoplankton, with some vascular plants such as seagrasses. In daylight the photosynthetic activity of these plants produces oxygen, which dissolves in the seawater and is used by marine animals. At night, photosynthesis stops, and the amount of dissolved oxygen declines. In the deep sea, where insufficient light penetrates
Sea
10135384
planet's air is a little less than the density of liquid water will the raindrops descend slowly; otherwise, they would come down like meteors and make life on Tenebra impossible. But life is possible on Tenebra. Although Clement doesn't say so explicitly, Tenebra's plants do not use photosynthesis. The optical depth of the atmosphere is too great for enough of Altair's light to reach the ground. Instead, Tenebra's plants use chemosynthesis based on the transformation of sulphur oxides. The process is much like that used by plants growing around the hydrothermal vents known as black smokers on the bottom of
Close to Critical
1666306
dioxide gain. Certain plants use alternative forms of photosynthesis, called Crassulacean acid metabolism (CAM) and C4. These employ physiological and anatomical adaptations to increase water-use efficiency and allow increased primary production to take place under conditions that would normally limit carbon fixation by C3 plants (the majority of plant species). In a reversal of the pattern on land, in the oceans, almost all photosynthesis is performed by algae, with a small fraction contributed by vascular plants and other groups. Algae encompass a diverse range of organisms, ranging from single floating cells to attached seaweeds. They include photoautotrophs from a variety
Primary production
331522
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
Photosynthesis
17758128
is evidence that the onset of C from is a biased signal, which only holds true for North America, from where most samples originate; emerging evidence suggests that grasslands evolved to a dominant state at least 15Ma earlier in South America. Evolution of photosynthesis The evolution of photosynthesis refers to the origin and subsequent evolution of photosynthesis, the process by which light energy synthesizes sugars from carbon dioxide, releasing oxygen as a waste product. The process of photosynthesis was discovered by Jan Ingenhousz, a Dutch-born British physician and scientist, first publishing about it in 1779. The first photosynthetic organisms probably
Evolution of photosynthesis
9537447
Grow light A grow light or plant light is an artificial light source, generally an electric light, designed to stimulate plant growth by emitting a light appropriate for photosynthesis. Grow lights are used in applications where there is either no naturally occurring light, or where supplemental light is required. For example, in the winter months when the available hours of daylight may be insufficient for the desired plant growth, lights are used to extend the time the plants receive light. If plants do not receive enough light, they will grow long and spindly. Grow lights either attempt to provide a
Grow light
12590363
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
Plant
3003035
2003 was actually a petroleum product. It is made by the catalytic hydration of ethylene with sulfuric acid as the catalyst. It can also be obtained via ethylene or acetylene, from calcium carbide, coal, oil gas, and other sources. of petroleum-derived ethanol are produced annually. The principal suppliers are plants in the United States, Europe, and South Africa. Petroleum derived ethanol (synthetic ethanol) is chemically identical to bio-ethanol and can be differentiated only by radiocarbon dating. Bio-ethanol is usually obtained from the conversion of carbon-based feedstock. Agricultural feedstocks are considered renewable because they get energy from the sun using photosynthesis,
Ethanol fuel
765318
photosynthesis. It reclaims the energy to power chemical reactions in cells. In so doing the carbon atoms and their electrons are combined with oxygen forming CO which is easily removed from both the cells and the organism. Plants use both processes, photosynthesis to capture the energy and oxidative metabolism to use it. Plant respiration is limited by the process of diffusion. Plants take in carbon dioxide through holes, known as stomata, that can open and close on the undersides of their leaves and sometimes other parts of their anatomy. Most plants require some oxygen for catabolic processes (break-down reactions that
Respiratory system
78050
radical polymerization, chain reactions and rearrangement reactions. Many important processes involve photochemistry. The premier example is photosynthesis, in which most plants use solar energy to convert carbon dioxide and water into glucose, disposing of oxygen as a side-product. Humans rely on photochemistry for the formation of vitamin D, and vision is initiated by a photochemical reaction of rhodopsin. In fireflies, an enzyme in the abdomen catalyzes a reaction that results in bioluminescence. Many significant photochemical reactions, such as ozone formation, occur in the Earth atmosphere and constitute atmospheric chemistry. In catalysis, the reaction does not proceed directly, but through reaction
Chemical reaction