T cellOne type of white blood cell that attacks virus-infected cells, foreign cells, and cancer cells.
T cell receptorAn antigen -binding protein, located on the surface of mammalian killer T cells, which mediates the cellular immune response.
T cellsA type of white blood cell that is of crucial importance to the immune system. Immature T cells migrate to the thymus gland in the upper chest cavity…
T lymphocyteOne type of white blood cell that attacks virus-infected cells, foreign cells, and cancer cells.
T RollsTransverse Rolls - elongated low-level clouds, arranged in parallel bands and aligned parallel to the low-level winds but perpendicular to the mid-level…
T-cell-mediated (cellular) immune responseThe synthesis of antigen-specific T cell receptors and the development of killer T cells in response to an encounter of immune system cells with an…
T-DNAThe DNA segment of the Ti plasmid, present in pathogenic Agrobacterium tumefaciens, that is transferred to plant cells and inserted into the plant's DNA…
T0, T1 and T2Successive generations of plants following a transformation event. The parent transformed plant is T0, its immediate progeny is T1, and the progeny of the…
T4 DNA ligaseAn enzyme, present in bacteria infected with bacteriophage T4, which catalyses the joining (ligation ) of, and repairs nicks in, duplex DNA molecules.
TagoutThe placement of a tagout device on an energy isolating device, in accordance with an established procedure, to indicate that the energy isolating device…
Tagout deviceA prominent warning device, such as a tag and a means of attachment, which can be securely fastened to an energy isolating device in accordance with an…
Tail CloudA horizontal, tail-shaped cloud (not a funnel cloud) at low levels extending from the precipitation cascade region of a supercell toward the wall cloud (i.
Tail-End CharlieSlang for the thunderstorm at the southernmost end of a squall line or other line or band of thunderstorms.
tailingThe in vitro addition, to the 3'-hydroxyl ends of a double-stranded DNA molecule, of multiple copies of a single nucleotide by the enzyme terminal…
TailingsSecond grade or waste material separated from pay material during screening or processing.
TailwaterThe water in the natural stream immediately downstream from a dam. The elevation of water varies with discharge from the reservoir.
Tailwater HeightHeight of water immediately downstream of the dam. (Various datums may be used.)
Tainter gateA term used by the Corps of Engineers to describe radial gates (see gate).
TakeUnder the Bald and Golden Eagle Protection Act, it means to pursue, shoot, shoot at, poison, wound, kill, capture, trap, collect, destroy, molest, or…
TakingA taking occurs when a government action violates the 5th Amendment property rights of a landowner by taking a piece of property without offering fair…
TallowAnimal fat that can be used to produce biodiesel.
TalusRock debris accumulated at the base of the cliff or slope from which they have broken off.
TampTo pound or press soil to compact. To firmly compact earth during backfilling.
TamperA tool for compacting soil in spots not accessible to rollers.
TampingA method of compacting soil using the impact of a power or hand tamper on the surface of the soil placed.
Tamping rollerOne or more steel drums, fitted with projection feet, used to densify soil. See sheepsfoot roller.
tandem repeatTwo (or more) contiguous identical DNA sequences. The orientation can be either head-to-tail, or head-to-head.
Tandem repeat sequencesMultiple copies of the same base sequence on a chromosome; used as markers in physical mapping. See also: physical map
TangentA line that touches a circle and is perpendicular to its radius at the point of contact.
tank bioreactorA fermentation vessel designed to grow large scale quantities of a micro-organism (bacteria, yeast or fungi).
Tankless Water HeaterA water heater that heats water before it is directly distributed for end use as required; a demand water heater.
tap rootRoot system in which the primary root has a much larger diameter than any lateral roots (e.g. carrot). Opposite: fibrous root.
TaprootA big root that grows downward from the base of a tree.
Taq polymeraseA heat-stable DNA polymerase isolated from the bacterium Therrnus aquaticus, used in PCR. (See Polymerase.)
TARA liquid product of thermal processing of carbonaceous materials.
Tar sandSwamp-like deposit of a mixture of fine clay, sand, water, and variable amounts of tar-like heavy oil known as bitumen.
TargetIn diagnostic tests, the molecule or nucleic acid sequence assayed in a sample.
target site duplicationA short sequence of DNA duplicated when a transposable element inserts at a new locus; usually found at each end of the insertion.
targeted drug deliveryA method of delivering the activated form of a drug molecule to the site in the body where it is needed, rather than allowing it reach the target by…
Targeted mutagenesisDeliberate change in the genetic structure directed at a specific site on the chromosome. Used in research to determine the targeted region's function.
targeting vectorA cloning vector carrying a DNA sequence capable of participating in a recombinational event at a specified chromosomal location in the host cell.
Task LightingAny light source designed specifically to direct light a task or work performed by a person or machine.
TATA boxAn adenine- and thymine-rich promoter sequence located 25-30 bp upstream of a gene, which is the binding site of RNA polymerase.
tautomeric shiftThe transfer of a hydrogen atom from one position in an organic molecule to another position.
tautomerismA type of isomerism in which the two isomers arising from a tautomeric shift are in equilibrium.
Tax Increment FinancingA program designed to leverage private investment for economic development projects in a manner that enhances the benefits accrued to the public interest.
TaxonomyThe science of categorization, or classification, of things based on a predetermined system.
Technical Response ServiceFor assistance with technical questions about alternative fuels and advanced vehicles, email the Technical Response Service at technicalresponse@icfi.
Technology transferThe process of providing the private sector access to technological advances developed by scientists in the Federal government. See also
TectonicRefers to the rock-deforming processes and resulting structures that occur over large sections of the lithosphere.
TectonicsThe science that deals with the structure of the earth's crust.
TeeA pipe fitting that has two threaded openings in line, and a third at right angles to them.
TeleconnectionLinkage between changes in atmospheric circulation occurring in widely separated parts of the globe.
telophaseThe last stage in each mitotic or meiotic division, in which the chromosomes coalesce at each pole of the dividing cell.
TEMPTemperature- A measure of the internal energy that a substance contains. This is the most measured quantity in the atmosphere.
temperate phageA phage (virus ) that invades but does not normally destroy (lyse) the host bacterial cell.
Temperature(Abbrev. TEMP)- The temperature is a measure of the internal energy that a substance contains. This is the most measured quantity in the atmosphere.
Temperature Humidity IndexAn index that combines sensible temperature and air humidity to arrive at a number that closely responds to the effective temperature; used to relate…
Temperature Inversion(surface-based or elevated) : a layer of the atmosphere in which air temperature increases with height.
Temperature RecoveryThe change in temperature over a given period of time. Generally, the period between late evening and sunrise.
Temperature ZonesIndividual rooms or zones in a building where temperature is controlled separately from other rooms or zones.
temperature-sensitive proteinA protein that is functional at one temperature but loses function at another (usually higher) temperature.
Temperature/Pressure Relief ValveA component of a water heating system that opens at a designated temperature or pressure to prevent a possible tank, radiator, or delivery pipe rupture.
Tempering ValveA valve used to mix heated water with cold in a heating system to provide a desired water temperature for end use.
Templatea standard shape that the race car must comply to be within the NASCAR rules. The template closely resembles the shape of the factory car.
Temporary irrigation service landIrrigable land for which a water supply is delivered under temporary arrangements. The acreage may vary from year to year.
Temporary structureAny structure that can be readily and completely dismantled and removed from the site between periods of actual use.
TensiometerInstrument, consisting of a porous cup filled with water and connected to a manometer or vacuum gauge, used for measuring the soilwater matrix potential.
TephraA general term for fragments of volcanic rock and lava, regardless of size, that are blasted into the air by explosions or carried upward by hot gases in…
Teratocarcinoma(TAYR-uh-toh-KAR-sih-NOH-muh) A type of germ cell cancer that usually forms in the testes (testicles).
TeratogenA drug or other agent that raises the incidence of congenital malformations.
TeratogenicSubstances such as chemicals or radiation that cause abnormal development of a embryo. See also: mutagen
Teratoma(tayr-uh-TOH-muh) A type of germ cell tumor that may contain several different types of tissue, such as hair, muscle, and bone.
Terminal Aerodrome ForecastThis NWS aviation product is a concise statement of the expected meteorological conditions at an airport during a specified period (usually 24 hours).
terminal budA branch tip, an undeveloped shoot containing rudimentary floral buds or leaves, enclosed within protective bud scales.