Science — page 119 of 132

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

Science terms

Telomerase An enzyme that maintains the structure of the telomere by adding the required repetitive sequences to the ends of eukaryotic chromosomes.
Telomere The end of a chromosome.
telophase The last stage in each mitotic or meiotic division, in which the chromosomes coalesce at each pole of the dividing cell.
TEMP Temperature- A measure of the internal energy that a substance contains. This is the most measured quantity in the atmosphere.
temperate phage A 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 Coefficient (of a solar photovoltaic cell) The amount that the voltage, current, and/or power output of a solar cell changes due to a change in the cell temperature.
Temperature Humidity Index An 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 Recovery The change in temperature over a given period of time. Generally, the period between late evening and sunrise.
Temperature Zones Individual rooms or zones in a building where temperature is controlled separately from other rooms or zones.
temperature-sensitive mutant An organism that can grow at one temperature but not at another.
temperature-sensitive protein A protein that is functional at one temperature but loses function at another (usually higher) temperature.
Temperature/Pressure Relief Valve A 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 Valve A valve used to mix heated water with cold in a heating system to provide a desired water temperature for end use.
Template a standard shape that the race car must comply to be within the NASCAR rules. The template closely resembles the shape of the factory car.
template strand See: anticoding strand.
Temporary irrigation service land Irrigable land for which a water supply is delivered under temporary arrangements. The acreage may vary from year to year.
Temporary structure Any structure that can be readily and completely dismantled and removed from the site between periods of actual use.
TEMPS temperatures
Tennessee Valley Authority (TVA) (TVA) A federal agency established in 1933 to develop the Tennessee river valley region of the southeastern U.S.
Tenocyte Tendon-producing cell.
Tensiometer Instrument, consisting of a porous cup filled with water and connected to a manometer or vacuum gauge, used for measuring the soilwater matrix potential.
Tephra A 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).
Teratogen A drug or other agent that raises the incidence of congenital malformations.
Teratogenic Substances 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 Forecast This NWS aviation product is a concise statement of the expected meteorological conditions at an airport during a specified period (usually 24 hours).
terminal bud A branch tip, an undeveloped shoot containing rudimentary floral buds or leaves, enclosed within protective bud scales.
Terminal structure Portion of spillway downstream from chute, tunnel or conduit, which generally dissipates or stills releases.
terminal transferase An enzyme that catalyses the addition of nucleotides to the 3' end of a DNA molecule.
terminal velocity The constant speed obtained by a falling object when the upward drag on the object balances the downward force of gravity.
terminalization Repelling movement of the centromeres of bivalents in the diplotene stage of the meiotic prophase, that appears to move visible chiasmata toward the ends…
Termination codon Any of three mRNA sequences (UGA, UAG, UAA) that do not code for an amino acid and thus signal the end of protein synthesis. Also known as stop codon.
termination signal In transcription, a nucleotide sequence that specifies RNA chain termination.
terminator 1. A DNA sequence just downstream of the coding segment of a gene, which is recognized by RNA polymerase as a signal to stop synthesizing mRNA. 2.
terminator codon See: stop codon.
terminator gene A specific variety-level genetic use restriction technology. A patented technique.
Terminator region A DNA sequence that signals the end of transcription.
Termite Shield A construction element that inhibits termites from entering building foundations and walls.
Terrace A step-like surface, bordering a valley floor or shoreline, that represents the former position of a floodplain, lake, or sea shore.
Terrain Topographic layout and features of a tract of land or ground.
Terrain Forced Flow An airflow that is modified or channeled as it passes over or around mountains or through gaps in a mountain barrier.
Terrestrial Things of the land.
Terrestrial radiation The total infrared radiation emitted by the Earth and its atmosphere in the temperature range of approximately 200 to 300 Kelvin.
terrigenous derived from land areas. For example, wind-blown dust from desert areas can settle into oceans and form terrigenous sediment on the sea floor.
Territorial communities Populations that function within a particular geographic area.
Tertiary period The earliest period of the Cenozoic era, beginning about 65 million years ago and ending 2.6 million years ago.
tertiary structure The three-dimensional conformation taken up by complete macromolecules as a result of intramolecular interactions, such as hydrogen-bonding.
Tertiary volcanics (Tv) (Tv) Volcanic rocks deposited during the Tertiary period (between 2.8 and 65 million years ago).
Test pit Pit dug for geologic investigation or inspection and testing of earthwork placement.
test-tube fertilization See: in vitro fertilization.
testcross A cross between a genetically unknown individual and a recessive tester to determine whether the individual in question is heterozygous or homozygous for…
testis (TES-tis) One of two egg-shaped glands inside the scrotum that produce sperm and male hormones. Also called testicle.
testosterone (tes-TOS-ter-own) A hormone that promotes the development and maintenance of male sex characteristics.
Tetracycline An antibiotic drug used to treat infection.
tetrad The four haploid cells formed after the second meiotic division in plants (pollen tetrads) or fungi (ascospores).
tetraploid An organism, or a tissue whose cells contain four haploid sets of chromosome s.
tetrasomic (Noun: tetrasome). Pertaining to a nucleus or an organism with four members of one of its chromosomes, whereas the remainder of its chromosome complement…
tetratype In fungi, a tetrad of spores that contains four different types; e.g. AB, aB, Ab and ab.
Texas Hooker Same as Panhandle Hook - low pressure systems that originate in the panhandle region of Texas and Oklahoma which initially move east and then "hook" or…
Texture The visual manifestations of light and shadow created by the variations in the surface of an object or landscape.
Texture contrasts Visual contrasts between different objects or landscapes resulting from different visual manifestations of the interplay of light and shadow created by…
TGGE Abbreviation for thermal gel gradient electrophoresis.
thallus Plant body without true roots, stems, or leaves.
Thalweg Deepest part of a river channel in a cross section of a river profile. The path of deepest flow. Line connecting the deepest points along a riverbed.
Theodolite An instrument used in surveying to measure horizontal and vertical angles with a small telescope that can move in the horizontal and vertical planes.
Theory most logical explanation of an event that occurs in nature.
therapeutic agent A compound used for the treatment of a disease or for improving the well-being of an organism. Synonyms: pharmaceutical agent, drug.
Therapeutic cloning The potential use of stem cells to grow, in vitro, tissue or organs for use in transplantation.
Therm A unit of heat containing 100,000 British thermal units (Btu).
Thermal A relatively small-scale, rising air current produced when the Earth's surface is heated.
Thermal Balance Point The point or outdoor temperature where the heating capacity of a heat pump matches the heating requirements of a building.
Thermal Belt A zone of high nighttime temperatures (and relatively low humidities) that is often experienced within a narrow altitude range on valley sidewalls…
Thermal Capacitance The ability of a material to absorb and store heat for use later.
Thermal cover Vegetative condition, generally with greater than 70% canopy closure and 40 feet in height, that can significantly ameliorate weather effects such as…
Thermal Efficiency A measure of the efficiency of converting a fuel to energy and useful work; useful work and energy output divided by higher heating value of input fuel…
Thermal Energy The energy developed through the use of heat energy.
Thermal Energy Storage The storage of heat energy during power provider off-peak times at night, for use during the next day without incurring daytime peak electric rates.
Thermal Envelope Houses An architectural design (also known as the double envelope house), sometimes called a "house-within-a-house," that employs a double envelope with a…
thermal gel gradient electrophoresis (Abbreviation: TGGE). A method for separating DNA fragments according to their mobility under increasingly denaturing conditions imposed by heat.
Thermal High Area of high pressure that is shallow in vertical extent and produced primarily by cold surface temperatures.
Thermal inertia The amount of heat energy that must be present in, preserved, or added to a system (in this case, a CSP facility) before it can function as designed.
Thermal Low Area of low pressure that is shallow in vertical extent and produced primarily by warm surface temperatures.
Thermal Mass Materials that store heat.
Thermal Resistance (R-Value) This designates the resistance of a material to heat conduction. The greater the R-value the larger the number.
Thermal resource A facility that produces electricity by using a heat engine to power an electric generator.
Thermal sand Sand used to dissipate heat away from buried electrical cables.
thermal shock Exposure to reduced or increased temperature for a significant period.
Thermal Storage Walls (Masonry or Water) A thermal storage wall is a south-facing wall that is glazed on the outside. Solar heat strikes the glazing and is absorbed into the wall, which conducts…
Thermal stratification The formation of layers of different temperatures in bodies of water. See stratification.
Thermal water A water body (usually a spring or its outflow) that is produced by geothermally heated groundwater.
Thermal Wind It is a theoretical wind that blows parallel to the thickness lines, for the layer considered, analogous to how the geostrophic wind blows parallel to the…
Thermal-electric powerplant A generating plant which uses heat to create steam driven electricity. Such plants may burn coal, gas, oil, wood, waste; or use nuclear, solar, and…
Thermally Driven Circulation A diurnally reversing closed cellular wind current resulting from horizontal temperature contrasts caused by different rates of heating or cooling over…
Thermistor A resistor whose resistance changes with temperature. Because of the known dependence of resistance on temperature, the resistor can be used as a…
Thermochemical Heat and pressure-based chemical reactions that produce energy. Through gasification (heating biomass by partial oxidation to produce synthesis gas) and…
thermochemical conversion The use of heat to change substances chemically to produce energy products.
Thermochemical conversion process Chemical reactions employing heat to produce fuels.