A free radical is a molecule with an odd number of electrons. Free radicals do not have a completed octet and often undergo vigorous redox reactions. Free radicals produced within cells can react with membranes, enzymes, and genetic material, damaging or even killing the cell. Free radicals have been implicated in a number of degenerative conditio...
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A type of unstable molecule that is made during normal cell metabolism (chemical changes that take place in a cell). Free radicals can build up in cells and cause damage to other molecules, such as DNA, lipids, and proteins. This damage may increase the risk of cancer and other diseases.
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See radical.
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http://www.chem.qmul.ac.uk/iupac/gtpoc/FG.html
A highly reactive chemical species carrying no charge and having a single unpaired electron in an orbital.
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http://www.chemistry-dictionary.com/definition/free+radical.php
A molecule, molecular fragment, or ion having one or more unpaired electrons, usually short-lived (less than 1 ms) and highly reactive. Free radicals can be produced by photolysis or pyrolysis in which a bond is broken without forming ions. In formulae, a free radical is conventionally indicated by ...
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A group of atoms that normally cluster with other atoms. They can exist on their own, but usually only for a fraction of a second. They are thought capable of damaging other cells.
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A molecule which has an odd number of electrons. The 'unpaired' electron feels lonely and wants to find a friend. If it finds something that might be willing to give it an electron it reacts very quickly with it. Molecules such as other radicals and alkenes turn out to be good things for radicals to attack. The reaction of radicals with the double ...
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A grouping of atoms that normally exists in combination with other atoms but can sometimes exist independently. They are generally very reactive in a chemical sense.
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A highly reactive chemical species carrying no charge and having a single unpaired electron in an orbital.
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A chemically active atom or molecular fragment containing a chemical charge due to an excess or deficient number of electrons. Radicals seek to receive or release electrons in order to achieve a more stable configuration, a process that can damage the large molecules within cells. ... See: Oxidation. ... (09 Oct 1997) ...
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a radical that carries an unpaired electron; such radicals are extremely reactive, with a very short half-life.
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An atom or group of atoms that has at least one unpaired electron and is therefore unstable and highly reactive. Free radicals are produced by the body as part of its normal activity (e.g., during an immune response) and are also present in the environment (e.g., cigarette smoke, asbestos). In animal tissues, excess free radicals can damage cells b...
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Highly reactive and usually short-lived molecular fragment with one or more unpaired electrons.
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A highly reactive molecule used to start the production of a polymer chain
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Free radicals can be formed in biological materials (e.g. DNA ) when they undergo Ionisation (by interaction with Ionising Radiation ). The free radical can be thought of as a reactive charged molecule which will readily combine with other cell constituents. A typical example is the ionisation of water which will produce H+ and OH- ions which can ....
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http://www.ionactive.co.uk/glossary_atoz.html?s=az&t=f
Type: Term Definitions: 1. a radical in its (usually transient) uncombined state; an atom or atom group carrying an unpaired electron and no charge; e.g., hydroxyl and methyl Free radicals may be involved as short-lived, highly active intermediates in various reactions in living tissue, notably in photosynthesis. The free radical nitric oxide, NO·...
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A highly reactive molecule used to start the production of a polymer chain.
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Group of atoms in particular combinations capable of free existence under special condition, usually for very short periods.
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[
n] - an atom or group of atoms with at least one unpaired electron
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see Oxygen free radical
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In chemistry, an atom or molecule that has an unpaired electron and is therefore highly reactive. Most free radicals are very short-lived. They are by-products of normal cell chemistry and rapidly oxidize other molecules they encounter. Free radicals are thought to do considerable damage. They are neutralized by protective enzymes. Free rad...
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A term used to describe atoms, molecules or ions with unpaired electrons and free radicals play an important role in a number of biological processes. However, the same free radicals can participate in unwanted side reactions, causing cell damage which contributes to illness, cancers, and ageing. Antioxidants are a major way to slow the impact of f...
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Are atoms, molecules or ions with unpaired electrons. Radicals (or free radicals) are believed to be involved in cancers and degenerative diseases. Not all free radical activity are damaging, some are necessary to life (intracellular killing of bacteria). It is the result of reactions between these free radicals and DNA resulting in mutation that c...
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an atom or molecule that bears an unpaired electron and is extremely reactive, capable of engaging in rapid chain reactions that destabilize other molecules and generate many more free radicals: in the body, deactivated by antioxidants, uric acid, and certain enzyme activities. Cf. diradical.
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https://www.infoplease.com/dictionary/free-radical
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