CAVUClear or Scattered Clouds (visibility greater than 10 mi.)
CBCumulonimbus cloud, characterized by strong vertical development in the form of mountains or huge towers topped at least partially by a smooth, flat…
CBDAbbreviation for Convention on Biological Diversity.
ccc DNAAbbreviation for covalently-closed circle DNA . See: circularization.
CCITTConsultative Committee for International Telephone & Telegraphy. Sets standards for phones, faxes, modems etc.
CCLConvective Condensation Level- The level in the atmosphere to which an air parcel, if heated from below, will rise dry adiabatically, without becoming…
CDa type of form designation such as Form CD435, meaning a Commerce Department form
CD moleculesAbbreviation for: cluster of differentiation molecules . Any group of surface antigens associated with a specific sub-population of T cells.
CDCClimate Diagnostic Center, the mission of the Climate Diagnostics Center (CDC) is to advance national capabilities to interpret the causes of observed…
CDDCooling Degree Days- A form of degree day used to estimate energy requirements for air conditioning or refrigeration.
cDNADNA synthesized from an RNA template using reverse transcriptase.
cDNA cloneA double-stranded cDNA molecule propagated in a vector, and used as a probe in RFLP analyses, as template for the production of EST sequences, and for…
cDNA cloningA method of cloning the coding sequence of a gene, starting with its mRNA transcript.
cDNA libraryA library composed of complementary copies of cellular mRNAs. (See Library.)
CDRAbbreviation for complementarity-determining regions.
CeilingIf there is an upper limit, or cap, on the interest rate you can be charged on an adjustable-rate loan, it's known as a ceiling.
Ceiling FanA mechanical device used for air circulation and to provide cooling.
CeilometerA device using a laser or other light source to determine the height of a cloud base.
CellThe fundamental level of structural organization in complex organisms. Eukaryotic cells contain a nucleus (with chromosome s) and cytoplasm with the…
Cell culture(SEL KUL-chur) The growth of microorganisms such as bacteria and yeast, or human, plant, or animal cells in the laboratory.
cell cycle(SEL SY-kul) The process a cell goes through each time it divides. The cell cycle consists of a series of steps during which the chromosomes and other…
cell differentiationThe process during which young, immature (unspecialized) cells take on individual characteristics and reach their mature (specialized) form and function.
Cell divisionFormation of two or more daughter cells from a single parent cell. The nucleus divides first, followed by the formation of a cell membrane between the…
cell fusionFormation in vitro of a single hybrid cell from the coalescence of two cells of different species origin.
cell generation timeThe interval between the beginning of consecutive divisions of a cell, equivalent to the time that it takes for a population of single-celled organisms to…
Cell line1. A cell lineage that can be maintained in vitro. Significant genetic changes can occur during lengthy periods in culture, so that the genotype of…
cell numberThe number of cells per unit volume of a culture.
cell plateThe precursor of the cell wall, formed at the beginning of cell division. The cell plate develops in the region of the equatorial plate and arises from…
cell sapWater and dissolved substances, sugar, amino acids, waste substances, etc., in the plant cell vacuole.
cell selectionThe process of selecting cells exhibiting specific traits within a group of genetically different cells.
cell strainAn in vitro culture initiated by asexual reproduction from a single cell. Such cell lines should represent a population of genetically homogenous cells.
cell suspensionCells in culture in moving or shaking liquid medium, often used to describe suspension cultures of single cells and cell aggregates.
Cell typeA specific subset of cells within the body, defined by their appearance, location and function.
cell wallA rigid external structure which surrounds plant cells. It is formed outside the plasmalemma and consists primarily of cellulose.
Cell-based therapiesTreatment in which stem cells are induced to differentiate into the specific cell type required to repair damaged or destroyed cells or tissues.
Cellular oncogene (proto-oncogene)A normal gene that when mutated or improperly expressed contributes to the development of cancer. (See Oncogene.)
Cellular therapyA field of medicine that uses cells to repair tissues that have been damaged by human disease or to generate new tissues with desired functional…
CellulaseEnzyme catalysing the breakdown of cellulose.
Cellulose(SEL-yoo-lose) A building block of plant cells and fiber. Cellulose cannot be digested by people, and is used to add bulk to the diet.
Cellulose InsulationA type of insulation composed of waste newspaper, cardboard, or other forms of waste paper.
cellulosomeA multi-protein aggregate present in some micro-organisms which degrade cellulose.
CelsiusThe standard scale used to measure temperature in most areas outside the United States.
Celsius (C), (°C)Unit of temperature. Degrees Celsius equals (5/9)x(degrees Fahrenheit-32).
CEMCivil Emergency Message. A message issued by the National Weather Service in coordination with Federal, state or local government to warn the general…
CenozoicAn era of geologic time from the beginning of the Tertiary period (65 million years ago) to the present. Its name is from the Greek and it means "new life.
Census blockCensus blocks are defined by the U.S. Bureau of Census and are the smallest geographic unit for which the Census Bureau tabulates data.
Census block groupsGeographic entities consisting of groups of individual census blocks. Census blocks are grouped together so that they contain between 250 and 550 housing…
CenterGenerally speaking, the vertical axis of a tropical cyclone, usually defined by the location of minimum wind or minimum pressure.
Center / Vortex FixThe location of the center of a tropical or subtropical cyclone obtained by reconnaissance aircraft penetration, satellite, radar, or synoptic data.
Center pivot irrigationA form of sprinkler irrigation consisting of several segments of pipe (usually galvanized steel or aluminum) that are joined together and supported by…
Centers of originUsually the location in the world where the oldest cultivation of a particular crop has been identified.
Centimeter BurstA solar radio burst in the centimeter wavelength range.
centiMorgan(Abbreviation: cM). Unit of map distance. For small recombination fractions, cM and % recombination frequency are equivalent.
Centimorgan (cM)A unit of measure of recombination frequency. One centimorgan is equal to a 1% chance that a marker at one genetic locus will be separated from a marker…
Central Arizona Project (CAP) Aqueduct(CAP)A 336-mi (541-km) long diversion canal operated by the Central Arizona Water Conservation District that diverts water from the Colorado River into central…
Central Business District (CBD)(CBD)The downtown retail trade and commercial area of a city or town, or an area of very high land valuation, traffic flow, and concentration of retail…
Central dogmaFrancis Crick's seminal concept that in nature genetic information generally flows from DNA to RNA to protein.
Central flywayAn important international migration route for many birds.
Central Heating SystemA system where heat is supplied to areas of a building from a single appliance through a network of ducts or pipes.
Central LineA central line is a flexible tube that is inserted near a patient's heart or into one of the large blood vessels near the heart.
Central Meridian Passage (CMP)In solar-terrestrial terms, the passage of an Active Region or other feature across the longitude meridian that passes through the apparent center of the…
central mother cellA subsurface cell located in a plant apical meristem and characterized by a large vacuole.
Central North Pacific BasinThe region north of the Equator between 140W and the International Dateline. The Central Pacific Hurricane Center (CPHC) in Honolulu, Hawaii is…
Central Power PlantA large power plant that generates power for distribution to multiple customers.
Centralized ExchangeA market where market participants execute all transactions with the central entity operating under a set of rules (product specifications, execution…
Centralized sewage treatmentThe collection and treatment of sewage from many sources to remove pollutants and pathogens.
centre of originThe geographic locations where a particular domesticated plant species originated.
centrifugal forceA force directed outward, away from the center of a rotating object; equal in magnitude to the centripetal force but in the opposite direction.
Centrifugal pumpA pump that moves water by centrifugal force developed by rapid rotation of an impeller.
CentrifugationSeparating molecules by size or density using centrifugal forces generated by a spinning rotor.
centrifugeA mechanical device which delivers the centrifugal forces necessary for centrifugation.
centrioleAn organelle in many animal cells that appears to be involved in the formation of the spindle during mitosis.
centripetal forceAn inward-directed force that confines an object to a circular path and is equal in magnitude to the centrifugal force but in the opposite direction.
CERCLASee Comprehensive Environmental Response, Compensation, and Liability Act of 1980
Cerebrospinal fluid(seh-REE-broh-SPY-nul...) The fluid that flows in and around the hollow spaces of the brain and spinal cord, and between two of the meninges (the thin…
Certification signatureCertification signatures are those of the persons who co-facilitated the risk analysis.
Certified water rightA State-issued document that serves as legal evidence that an approved application has been physically developed and the water put to beneficial use.