A vitamin is an organic compound An organic compound is any member of a large class of chemical compounds whose molecules contain carbon. For historical reasons discussed below, a few types of compounds such as carbonates, simple oxides of carbon and cyanides, as well as the allotropes of carbon, are considered inorganic. The distinction between "organic" and " required as a nutrient A nutrient is a chemical that an organism needs to live and grow or a substance used in an organism's metabolism which must be taken in from its environment. Nutrients are the substances that enrich the body. They build and repair tissues, give heat and energy, and regulate body processes. Methods for nutrient intake vary, with animals and in tiny amounts by an organism In biology, an organism is any contiguous living system . In at least some form, all organisms are capable of response to stimuli, reproduction, growth and development, and maintenance of homoeostasis as a stable whole. An organism may either be unicellular (single-celled) or be composed of, as in humans, many trillions of cells grouped into.[1] In other words, an organic chemical compound (or related set of compounds) is called a vitamin when it cannot be synthesized Biosynthesis is an enzyme-catalyzed process in cells of living organisms by which substrates are converted to more complex products. The biosynthesis process often consists of several enzymatic steps in which the product of one step is used as substrate in the following step. Examples for such multi-step biosynthetic pathways are those for the in sufficient quantities by an organism, and must be obtained from the diet. Thus, the term is conditional both on the circumstances and the particular organism. For example, ascorbic acid Ascorbic acid is a sugar acid with antioxidant properties. Its appearance is white to light-yellow crystals or powder, and it is water-soluble. One form of ascorbic acid is commonly known as vitamin C. The name is derived from a- and scorbutus (scurvy), the disease caused by a deficiency of vitamin C. In 1937 the Nobel Prize for chemistry was (vitamin C Vitamin C or L-ascorbic acid or L-ascorbate is an essential nutrient for humans and certain other animal species, in which it functions as a vitamin. In living organisms, ascorbate is an anti-oxidant, since it protects the body against oxidative stress. It is also a cofactor in at least eight enzymatic reactions, including several collagen) is a vitamin for humans, but not for most other animals, and biotin Biotin is a water-soluble B-complex vitamin that is composed of an ureido (tetrahydroimidizalone) ring fused with a tetrahydrothiophene ring. A valeric acid substituent is attached to one of the carbon atoms of the tetrahydrothiophene ring. Biotin is a coenzyme in the metabolism of fatty acids and leucine, and it plays a role in gluconeogenesis and vitamin D Vitamin D is a group of fat-soluble secosteroids, the two major physiologically relevant forms of which are vitamin D2 and vitamin D3 (cholecalciferol). Vitamin D without a subscript refers to either D2 or D3 or both. Vitamin D3 is produced in the skin of vertebrates after exposure to ultraviolet B light from the sun or artificial sources, and are required in the human diet only in certain circumstances. By convention, the term vitamin does not include other essential nutrients An essential nutrient is a nutrient required for normal body functioning that either cannot be synthesized by the body at all, or cannot be synthesized in amounts adequate for good health , and thus must be obtained from a dietary source. Essential nutrients are also defined by the collective physiological evidence for their importance in the diet, such as dietary minerals Dietary minerals are the chemical elements required by living organisms, other than the four elements carbon, hydrogen, nitrogen, and oxygen present in common organic molecules. The term "mineral" is archaic, since the intent of the definition is to describe ions , not chemical compounds or actual minerals. Examples include calcium, (which are inorganic), essential fatty acids Essential fatty acids, or EFAs, are fatty acids that humans and other animals must ingest for good health because the body requires them but can't make them from other food components. The term refers to fatty acids required for biological processes, and not those that only act as fuel or essential amino acids An essential amino acid or indispensable amino acid is an amino acid that cannot be synthesized de novo by the organism , and therefore must be supplied in the diet (which are needed in larger amounts than vitamins), nor does it encompass the large number of other nutrients that promote health, but are otherwise required less often.[2] Thirteen vitamins are presently universally recognized.
Vitamins are classified by their biological and chemical activity, not their structure. Thus, each "vitamin" refers to a number of vitamer A vitamer of a particular vitamin is any of the chemical compounds which exhibit vitamin activity. Very commonly "vitamins" are not single compounds, but rather each vitamin, which is defined by its biological activity, not its structure, is actually represented by a number of substances, each of which shows vitamin activity. These compounds that all show the biological activity associated with a particular vitamin. Such a set of chemicals are grouped under an alphabetized vitamin "generic descriptor" title, such as "vitamin A Vitamin A is a vitamin that is needed by the retina of the eye in the form of a specific metabolite, the light-absorbing molecule retinal. This molecule is absolutely necessary for both scotopic and color vision. In another version the vitamin is necessary for the function of the reproductive systems of both male and female mammals. Vitamin A also", which includes the compounds retinal Retinal, also called retinaldehyde or vitamin A aldehyde, is one of the many forms of vitamin A . Retinal is a polyene chromophore, and bound to proteins called opsins, is the chemical basis of animal vision. Bound to proteins called type 1 rhodopsins, retinal allows certain microorganisms to convert light into metabolic energy, retinol Retinol, is one of the animal forms of vitamin A. It is a diterpenoid and an alcohol. It is convertable to other forms of vitamin A, but as retinol it is thought to serve an irreplaceable vitamin function in the reproductive tracts of male and female mammals. The retinyl ester derivative of the alcohol serves as the storage form of the vitamin in, and four known carotenoids Carotenoids are tetraterpenoid organic pigments that are naturally occurring in the chloroplasts and chromoplasts of plants and some other photosynthetic organisms like algae, some types of fungus some bacteria and at least one species of aphid. Carotenoids are generally not manufactured by species in the animal kingdom, although one species of. Vitamers by definition are convertible to the active form of the vitamin in the body, and are sometimes inter-convertible to one another, as well.
Vitamins have diverse biochemical functions. Some have hormone-like functions as regulators of mineral metabolism (e.g. vitamin D), or regulators of cell and tissue growth and differentiation (e.g. some forms of vitamin A Vitamin A is a vitamin that is needed by the retina of the eye in the form of a specific metabolite, the light-absorbing molecule retinal. This molecule is absolutely necessary for both scotopic and color vision. In another version the vitamin is necessary for the function of the reproductive systems of both male and female mammals. Vitamin A also). Others function as antioxidants An antioxidant is a molecule capable of inhibiting the oxidation of other molecules. Oxidation is a chemical reaction that transfers electrons from a substance to an oxidizing agent. Oxidation reactions can produce free radicals. In turn, these radicals can start chain reactions that damage cells. Antioxidants terminate these chain reactions by (e.g. vitamin E Vitamin E is a generic term for tocopherols and tocotrienols. Vitamin E is a family of α-, β-, γ-, and δ- tocopherols and corresponding four tocotrienols. Vitamin E is a fat-soluble antioxidant that stops the production of reactive oxygen species formed when fat undergoes oxidation. Of these, α-tocopherol (also written as alpha-tocopherol) and sometimes vitamin C Vitamin C or L-ascorbic acid or L-ascorbate is an essential nutrient for humans and certain other animal species, in which it functions as a vitamin. In living organisms, ascorbate is an anti-oxidant, since it protects the body against oxidative stress. It is also a cofactor in at least eight enzymatic reactions, including several collagen).[3] The largest number of vitamins (e.g. B complex The B vitamins are eight water-soluble vitamins that play important roles in cell metabolism. The B vitamins were once thought to be a single vitamin, referred to as vitamin B . Later research showed that they are chemically distinct vitamins that often coexist in the same foods. In general, supplements containing all eight are referred to as a vitamins) function as precursors for enzyme cofactors A cofactor is a non-protein chemical compound that is bound to a protein and is required for the protein's biological activity. These proteins are commonly enzymes, and cofactors can be considered "helper molecules" that assist in biochemical transformations. Cofactors can also be classified depending on how tightly they bind to an, that help enzymes in their work as catalysts Catalysis is the change in rate of a chemical reaction due to the participation of a substance called a catalyst. Unlike other reagents that participate in the chemical reaction, a catalyst is not consumed by the reaction itself. A catalyst may participate in multiple chemical transformations. Catalysts that speed the reaction are called positive in metabolism Metabolism is the set of chemical reactions that happen in living organisms to maintain life. These processes allow organisms to grow and reproduce, maintain their structures, and respond to their environments. Metabolism is usually divided into two categories. Catabolism breaks down organic matter, for example to harvest energy in cellular. In this role, vitamins may be tightly bound to enzymes Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process are called substrates, and the enzyme converts them into different molecules, called the products. Almost all processes in a biological cell need enzymes to occur at significant rates. Since enzymes are selective for their as part of prosthetic groups A cofactor is a non-protein chemical compound that is bound to a protein and is required for the protein's biological activity. These proteins are commonly enzymes and cofactors can be considered "helper molecules" that assist in biochemical transformations. Cofactors can also be classified depending on how tightly they bind to an enzyme,: for example, biotin Biotin is a water-soluble B-complex vitamin that is composed of an ureido (tetrahydroimidizalone) ring fused with a tetrahydrothiophene ring. A valeric acid substituent is attached to one of the carbon atoms of the tetrahydrothiophene ring. Biotin is a coenzyme in the metabolism of fatty acids and leucine, and it plays a role in gluconeogenesis is part of enzymes involved in making fatty acids In chemistry, especially biochemistry, a fatty acid is a carboxylic acid with a long unbranched aliphatic tail , which is either saturated or unsaturated. The most occurring natural fatty acids have an even number of carbon atoms because their biosynthesis involves acetyl-CoA, a coenzyme carrying a two-carbon-atom group (see fatty acid synthesis). Alternately, vitamins may also be less tightly bound to enzyme catalysts as coenzymes A cofactor is a non-protein chemical compound that is bound to a protein and is required for the protein's biological activity. These proteins are commonly enzymes, and cofactors can be considered "helper molecules" that assist in biochemical transformations. Cofactors can also be classified depending on how tightly they bind to an, detachable molecules which function to carry chemical groups or electrons between molecules. For example, folic acid Folic acid and folate (the naturally occurring form), as well as pteroyl-L-glutamic acid and pteroyl-L-glutamate, are forms of the water-soluble vitamin B9. Folic acid is itself not biologically active, but its biological importance is due to tetrahydrofolate and other derivatives after its conversion to dihydrofolic acid in the liver carries various forms of carbon group – methyl In chemistry, a methyl group is a hydrophobic alkyl functional group named after methylene (RC , formyl An aldehyde is an organic compound containing a formyl group. This functional group, with the structure R-CHO, consists of a carbonyl centre bonded to hydrogen and an R group. The group without R is called the aldehyde group or formyl group. Aldehydes differ from ketones in that the carbonyl is placed at the end of a carbon skeleton rather than and methylene Methylene groups in a chain or ring contribute to its size and lipophilicity. Methylene was also the old original name for methanol - in the cell. Although these roles in assisting enzyme-substrate reactions are vitamins' best-known function, the other vitamin functions are equally important.[4]
Until the mid-1930s, when the first commercial yeast-extract and semi-synthetic vitamin C supplement tablets were sold, vitamins were obtained solely through food intake, and changes in diet (which, for example, could occur during a particular growing season) can alter the types and amounts of vitamins ingested. Vitamins have been produced as commodity chemicals In chemistry, a chemical substance is a material with a specific chemical composition and made widely available as inexpensive semisynthetic and synthetic-source multivitamin A multivitamin is a preparation intended to supplement a human diet with vitamins, dietary minerals and other nutritional elements. Such preparations are available in the form of tablets, capsules, pastilles, powders, liquids and injectable formulations. Other than injectable formulations, which are only available and administered under medical dietary supplements, since the middle of the 20th century.
The term vitamin was historically derived from "vitamine," a combination word from vita and amine, meaning amine of life, because it was suggested in 1912 that the organic micronutrient food factors which prevented beriberi and perhaps other similar dietary-deficiency diseases, might be chemical amines Amines are organic compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are derivatives of ammonia, wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group. Important amines include amino acids, biogenic amines, trimethylamine, and aniline; see Category:Amines for. This proved incorrect for the micronutrient class, and the word was shortened to vitamin.
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New York Post Roger Clemens, accused of using steroids, said he only had been injected with the vitamin and lidocaine. When Rafael Palmeiro tested positive for a steroids ... REPORT: MLB investigating Ivan Nova, Wilkin De La Rosa for injections while ... The Trentonian Ivan Nova delivers again as Yankees beat White Sox, 2-1 The Star-Ledger - NJ.com
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the last couple of days has allowed Jill to collect some more Vitamin D and looking at the sun this morning we will be able to be out in the sun this afternoon See you next week on the net
