Science — page 7 of 132

13,110 terms including subtopics (0 terms filed directly here)

Subtopics

Science terms

  1. Annex I Countries/Parties Group of countries included in Annex I (as amended in 1998) to the United Nations Framework Convention on Climate Change, including all the developed…
  2. Annex I Parties Industrialized countries that, as parties to the Framework Convention on Climate Change, have pledged to reduce their greenhouse gas emissions by the year…
  3. Annexation A change in existing community boundaries resulting from the incorporation of additional land.
  4. Annihilated/annihilation A process in which a particle meets its corresponding antiparticle and both disappear.
  5. annotation Adding pertinent information such as gene coded for, amino acid sequence, or other commentary to the database entry of raw sequence of DNA bases.
  6. annual For FDM purposes, you are an annual filer if last year you filed an OGE Form 450 (or an OGE Form 450-A).
  7. Annual energy cost Variable costs relating to energy production in a year, usually espressed in mills per kilowatt-hour.
  8. Annual failure probability The probability of the load multiplied by the probability of failure.
  9. Annual Flood The maximum discharge peak during a given water year (October 1 - September 30).
  10. Annual Fuel Utilization Efficiency (AFUE) (AFUE) The measure of seasonal or annual efficiency of a residential heating furnace or boiler.
  11. Annual inspection (AI) Annual inspections of a dam and appurtenant facilities are conducted by the local operating office.
  12. Annual load factor This factor is equal to energy generated in a year divided by the product of the peak demand for that year and the number of total hours in a year.
  13. Annual Load Fraction That fraction of annual energy demand supplied by a solar system.
  14. Annual operating cost This is a general term which is sometimes called annual operating expense and includes all annual operation and maintenance expense, wheeling, purchased…
  15. Annual Solar Savings The annual solar savings of a solar building is the energy savings attributable to a solar feature relative to the energy requirements of a non-solar…
  16. Annual work plan Annual budget document that describes proposed work to be performed at a specific Bureau of Reclamation project, and details the amount of funds required.
  17. Annualized loss of life The sum of the probability of dam failure multiplied by the annual probability of the loading and the estimated number of lives that would be lost…
  18. Annular Ring-shaped.
  19. Annular space A ring-shaped space located between two circular objects, such as two pipes.
  20. Anode The positive pole or electrode of an electrolytic cell, vacuum tube, etc. (see also sacrificial anode).
  21. anomalies The departures of temperature, precipitation, or other weather elements from long-term averages.
  22. ANOMALOUS PROPAGATION (AP) Non-standard atmospheric temperature or moisture gradients will cause all or part of the radar beam to propagate along a non-normal path.
  23. Anomaly Something that is out of the ordinary. For example if in a set of 1000 two winged, two legged, one headed, (essentially normal) chickens, one of them had…
  24. anonymous DNA marker A detectable by virtue of variation in its sequence. The function (if any) of the sequence is unknown.
  25. Anoxic Without oxygen.
  26. ANSI American National Standards Institute - a private, non-profit organization that administers and coordinates the U.S.
  27. antagonism An interaction between two organisms (e.g. moulds or bacteria) in which the growth of one is inhibited by the other. Opposite: synergism.
  28. antagonist In medicine, a substance that stops the action or effect of another substance. For example, a drug that blocks the stimulating effect of estrogen on a…
  29. Antarctic "Ozone Hole" Refers to the seasonal depletion of stratospheric ozone in a large area over Antarctica. See ozone, ozone layer.
  30. Antecedent flood A flood or series of floods assumed to occur prior to the occurrence of an inflow design flood (IDF).
  31. Antecedent Precipitation Index (API) (API) An index of moisture stored within a drainage basin before a storm.
  32. Antedecent Precipitation Index (Abbrev. API) - an index of moisture stored within a drainage basin before a storm.
  33. ANTENNA GAIN The measure of effectiveness of a directional antenna as compared to an isotropic radiator, maximum value is called antenna gain by convention.
  34. Anterior visceral endoderm (AVE) Specific tissue structure arising in the early embryo that helps establish the anterior-posterior axis of the organism.
  35. Anthelion A luminous white spot that appears on the parhelic circle at the same altitude as the sun and 180 degrees from it in azimuth.
  36. anther The upper part of a stamen, containing pollen sacs within which the pollen develops and matures.
  37. anther culture The aseptic culture of immature anthers to generate haploid plants from microspores via androgenesis.
  38. anthesis The period during which anthers bear mature and functional pollen.
  39. anthocyanin A water-soluble blue, purple or red flavonoid pigments found in vacuoles of cells of certain plants.
  40. Anthracite A hard, black, lustrous coal containing a high percentage of fixed carbon and a low percentage of volatile matter. Often referred to as hard coal.
  41. Anthracite (coal) A hard, dense type of coal, that is hard to break, clean to handle, difficult to ignite, and that burns with an intense flame and with the virtual absence…
  42. Anthropogenic Referring to alterations in the environment due to the presence or activities of humans.
  43. Anthropogenic emissions Made by people or resulting from human activities. Usually used in the context of emissions that are produced as a result of human activities.
  44. Anthropogenic Source A pollutant source caused or produced by humans.
  45. Anthropomorphic Described or thought of as having human form or human attributes.
  46. Anthropomorphism Ascribing human qualities, characteristics, or behavior to inanimate objects, animals, or natural phenomena.
  47. anti-idiotype antibody An antibody, produced by an organism, which specifically binds to the binding site of an antibody developed by that organism against a foreign antigen.
  48. Anti-oncogene See Recessive oncogene.
  49. Anti-Seep Collar A projecting collar of steel or concrete built around the outside of a pipe, tunnel, or conduit under or through an embankment dam to lengthen the seep…
  50. anti-terminator A protein which enables RNA polymerase to ignore certain transcriptional stop or termination signals and thereby produce longer than normal transcripts.
  51. Anti-wind The upper or return branch of an along-valley wind system, as confined within a valley, and blowing in a direction opposite to the winds in the lower…
  52. antiauxin A chemical that interferes with the auxin response, sometimes by the prevention of auxin transport. Some antiauxins may promote morphogenesis in vitro (e.
  53. antibiosis The prevention of growth or development of an organism by a substance or another organism.
  54. Antibiotic A drug used to treat infections caused by bacteria and other microorganisms. Atrial Fibrillation: A heart rhythm disorder (arrhythmia) that usually…
  55. Antibiotic resistance The ability of a microorganism to produce a protein that disables an antibiotic or prevents transport of the antibiotic into the cell.
  56. antibiotic resistance marker gene (Abbreviation: ARMG). Genes (usually of bacterial origin) used as selection markers in transgenesis, because their presence allows cell survival in the…
  57. Antibody (AN-tee-BAH-dee) A type of protein made by plasma cells (a type of white blood cell) in response to an antigen (foreign substance).
  58. Antibody (Immunoglobulin) A protein produced by the white blood cells (leukocytes) to battle foreign substances, such as bacteria, that enter the body.
  59. antibody binding site The part of an antibody that binds to the antigenic determinant. See: complementarity-determining regions. Synonym: paratope.
  60. antibody class The class to which an antibody belongs, depending on the type of heavy chain present.
  61. antibody structure Describes the molecular architecture of an antibody, which consists of two identical "light" chains and two identical "heavy" chains and has two antigen…
  62. antibody-mediated immune response The synthesis of antibodies by B cells in response to an encounter of the cells of the immune system with a foreign antigen.
  63. Anticipation A situation that exists when claimed invention is not novel in view of the prior art.
  64. anticlinal The orientation of cell wall or plane of cell division perpendicular to the surface. Opposite: periclinal.
  65. Anticline A fold in rocks that curves upward in a convex way. Upward fold in rock layers that creates an arched or domelike uplift of sedimentary layers.
  66. anticoding strand The DNA strand used as template for transcription. The resulting mRNA is complementary in sequence to that of the anticoding strand.
  67. Anticodon A nucleotide base triplet in a transfer RNA molecule that pairs with a complementary base triplet, or codon, in a messenger RNA molecule.
  68. Anticyclogenesis The formation or intensification of an anticyclone or high pressure center.
  69. Anticyclone A large-scale circulation of winds around a central region of high atmospheric pressure, clockwise in the Northern Hemisphere, counterclockwise in the…
  70. Anticyclonic circulation Anticyclonic circulation System of air movements (atmospheric circulation) associated with an anticyclone, which is clockwise in the Northern Hemisphere…
  71. Anticyclonic Rotation Rotation in the opposite sense as the Earth's rotation, i.e., clockwise in the Northern Hemisphere as would be seen from above.
  72. Antifreeze Solution A fluid, such as methanol or ethylene glycol, added to vehicle engine coolant, or used in solar heating system heat transfer fluids, to protect the…
  73. Antigen A substance that causes the immune system to make a specific immune response.
  74. Antigen presenting cells (APCs) One of a variety of cells within the body that can process antigens and display them on their surface in a form recognizable by T cells.
  75. Antigenic determinant A surface feature of a microorganism or macromolecule, such as a glycoprotein, that elicits an immune response.
  76. Antigenic switching The altering of a microorganism's surface antigens through genetic rearrangement, to elude detection by the host's immune system.
  77. antihaemophilic factor VIII See: antihaemophilic globulin.
  78. antihaemophilic globulin (Abbreviation AHG). One of the blood clotting factors, a soluble protein that causes the fibrin matrix of a blood clot to form.
  79. Antilles Current A current which originates in the vicinity of the Leeward Islands as part of the Atlantic North Equatorial Current.
  80. Antimatter Matter made up of elementary particles whose masses are identical to their normal-matter counterparts but whose other properties, such as electric charge…
  81. Antimicrobial agent Any chemical or biological agent that harms the growth of microorganisms.
  82. antinutrient Compounds that inhibit the normal uptake or utilization of nutrients.
  83. antioxidant (AN-tee-OK-sih-dent) A substance that protects cells from the damage caused by free radicals (unstable molecules made by the process of oxidation during…
  84. antiparallel orientation The normal arrangement of the two strands of a double-stranded DNA molecule, and of other nucleic-acid duplexes (DNA -RNA, RNA -RNA ), in which the two…
  85. Antiparticle/antiquark/antielectron For most particle types there is another particle type that has exactly the same mass but the opposite value of all other charges.
  86. Antireflection Coating A thin coating of a material applied to a photovoltaic cell surface that reduces the light reflection and increases light transmission.
  87. Antisense The non-coding strand in double-stranded DNA. The antisense strand serves as the template for mRNA synthesis. See also cell
  88. antisense DNA (AN-tee-sents …) Small pieces of DNA that can bind to specific molecules of RNA and block the cell's ability to use the RNA to make a protein.
  89. antisense gene A gene that produces an mRNA complementary to the transcript of a normal gene (usually constructed by inverting the coding region relative to the promoter…
  90. antisense RNA (AN-tee-sents …) Small pieces of RNA that can bind to specific molecules of RNA and block the cell's ability to use the RNA to make a protein.
  91. antisense therapy The in vivo treatment of a genetic disease by blocking translation of a protein with a DNA or an RNA sequence that is complementary to a specific mRNA.
  92. antiseptic Any substance that kills or inhibits the growth of disease-causing micro-organism (a micro-organism capable of causing sepsis), but is essentially…
  93. antiserum The fluid portion of the blood of an immunized animal (after coagulation of the blood), which retains any antibodies.
  94. antitranspirant A compound designed to reduce plant transpiration. Applied to the leaves of newly transplanted trees, shrubs etc., or cuttings in lieu of misting.
  95. antixenosis The modification of the behaviour of an organism by a substance or another organism.
  96. Anvil The flat, spreading top of a cumulonimbus cloud, often shaped like an anvil. Thunderstorm anvils may spread hundreds of miles downwind from the…
  97. Anvil Crawler [Slang], a lightning discharge occurring within the anvil of a thunderstorm, characterized by one or more channels that appear to crawl along the…
  98. Anvil Dome A large overshooting top or penetrating top.
  99. Anvil Rollover Slang for a circular or semicircular lip of clouds along the underside of the upwind part of a back-sheared anvil, indicating rapid expansion of the anvil.
  100. Anvil Zits Slang for frequent (often continuous or nearly continuous), localized lightning discharges occurring from within a thunderstorm anvil.