Science terms starting with G

542 terms

Glory An optical effect characterized by concentric rings of color (red outermost and violet innermost) surrounding the shadow of an observer's head when the…
GLP Abbreviation for good laboratory practice.
GLS (Great Lakes Storm Summary) A National Weather Service forecast product providing updated information whenever a storm warning is in effect on any of the…
Glucagon A hormone produced by the pancreas that increases the level of glucose (sugar) in the blood.
glucan The polymer of glucose with a repeating unit of C6H10O5. Cellulose is a form of glucan. Can be hydrolyzed to glucose. (Source: Voet, D.; Voet, J. G.
glucocorticoid A compound that belongs to the family of compounds called corticosteroids (steroids).
glucose A type of sugar; the chief source of energy for living organisms.
glucose invertase An enzyme that catalyses the hydrolysis of sucrose into its component monosaccharides, glucose and fructose.
glucose isomerase An enzyme that catalyses the interconversion of the two sugars, glucose and fructose.
glucosinolates A class of molecules produced in the seeds and green tissue of a range of plants, in particular brassicas.
glucuronidase See: beta-glucuronidase.
Gluon The carrier particle of the strong interactions. It holds quarks together and the atom's nucleus together.
gluten A mixture of two seed storage protein classes, gliadin and glutenin, found in the endosperm of cereal (particularly wheat) grain.
glycerin (C3H8O3) A liquid by-product of biodiesel production. Glycerin is used in the manufacture of dynamite, cosmetics, liquid soaps, inks, and lubricants.
glycoalkaloids A group of modified alkaloids, including solanine and tomatine, having a range of toxic effects in humans and other species.
glycoform One of several structures possible for a given glycoprotein, determined by the type and position of attachment of the component oligosaccharide (s).
glycolysis A process in which glucose (sugar) is partially broken down by cells in enzyme reactions that do not need oxygen.
glycoprotein A protein that has sugar molecules attached to it.
glycoprotein remodelling The use of restriction endoglycosidases to enzymatically remove oligosaccharide branches from glycoprotein molecules.
glycosylation The covalent addition of sugar or sugar-related molecules to other classes of molecule, including proteins or nucleic acids.
glyphosate An active ingredient in some herbicides, killing plants by inhibiting the activity of plant enolpyruvyl-shikimate 3-phosphate synthase.
glyphosate oxidase An enzyme which catalyses the break-down of glyphosate, discovered in a strain of Pseudomonas bacteria which were found to produce unusually large amounts…
glyphosate oxidoreductase An enzyme from the micro-organism Ochrobactrum anthropi, which catalyses the break-down of glyphosate.
GM food Abbreviation for genetically modified food. Food that contains above a certain legal minimum content of raw material obtained from genetically modified…
GMDSS (Global Maritime Distress and Safety System)- The Global Maritime Distress and Safety System (GMDSS) is intended to provide more effective and efficient…
GMN On a buoy report, the minute of the hour that the GSP occurred, reported at the last hourly 10-minute segment.
GMO Genetically modified organism.
GMP Abbreviation for 1. guanosine 5'-monophosphate. Synonym: guanylic acid. 2. good manufacturing practice.
GMT Greenwich Mean Time (now known as Universal Coordinated Time)
GND Ground
Gneiss Metamorphic rock that displays distinct banding of light and dark mineral layers.
GNRL General
gobar See: biogas.
GOES Geostationary Operational Environmental Satellite- Satellites orbiting at 22,370 miles above the Earth's surface with the same rotational velocity as the…
GOES Data Collection System (DCS) A data collection system under NESDIS which is comprised of the DCPs, and the NESDIS Command and Data Acquisition (CDA) System components.
Goggle valve. See ring follower gate.
golden rice A biotechnology-derived rice, which contains large amounts of beta carotene (a precursor of vitamin A) in its seeds.
Golgi apparatus An assembly of vesicles and folded membranes within the cytoplasm of plant and animal cells that stores and transports secretory products (such as enzymes…
GoMoos Gulf Of Maine Ocean Observing System
gonad The part of the reproductive system that produces and releases eggs (ovary) or sperm (testicle/testis).
Gonadal ridge Anatomic site in the early fetus where primordial germ cells (PGCs) are formed.
Gonadal ridges Embryonic structures arising in humans at about five weeks, eventually developing into gonads (either testes or ovaries).
Gonads The embryonic sex gland before it becomes a definitive testis or ovary.
Good Laboratory Practice an approved method to perform a basic operation, activity, or service in a laboratory which influences or enhances the quality of its output.
good manufacturing practice (Abbreviation: GMP). Codes of practice designed to reduce to a minimum the chance of procedural or instrument/manufacturing plant problems which could…
Goosecoid Gene that encodes a transcription factor that is important for determining craniofacial orientation and features in the vertebrate embryo.
Governor A device used to regulate motor speed, or, in a wind energy conversion system, to control the rotational speed of the rotor.
GPS An acronym for Global Positioning System. A network of satellites which provide extremely accurate position and time information.
gr/SCF Grains of pollutant per standard cubic foot of gas. A measure of dust particles in a gas stream.
Graben Down-dropped block of rock bounded on both sides by faults. See fault-block.
Graben (fault-bounded basins) An elongated crustal block that is relatively depressed (down dropped) between two parallel normal faults or horsts. See also Half-graben
GRAD Gradient- A rate of change with respect to distance of a variable quantity, as temperature or pressure, in the direction of maximum change.
Gradation Proportion of material of each grain-size present in a given soil. The proportions by mass of a soil or fragmented rock distributed in specified…
Grade (pitch) The elevation of a surface or a surface slope. The elevation of the invert of the bottom of a pipeline, canal, culvert, or conduit.
Grade stake A stake indicating the amount of cut or fill required to bring the ground to a specified level.
Graded stream Streams that receive and carry away equal amounts of sediment.
Grader A machine with a centrally located blade that can be angled to cast to either side, with independent hoist control on each side.
Gradient General slope or rate of change in vertical elevation per unit of horizontal distance of water surface of a flowing stream.
Gradient High Winds These high winds usually cover a large area and are due to synoptic-scale, extra-tropical low pressure systems.
Gradient wind Gradient wind The same as geostrophic wind, but blowing parallel to curved isobars or contours.
Gradual Commencement In solar-terrestrial terms, the commencement of a geomagnetic storm that has no well-defined onset
graft Healthy skin, bone, or other tissue taken from one part of the body and used to replace diseased or injured tissue removed from another part of the body.
graft chimera A plant which is a mosaic of two sorts of tissue differing in genetic constitution and assumed to have arisen as the result of a nuclear fusion following…
graft hybrid An individual formed from graft (2) and stock showing the characteristics of both progenitors. See: graft chimera.
graft inoculation test A test based on the use of a suspected viral carrier which is grafted to an indicator plant.
graft union The point at which a scion from one plant is joined to a rootstock from another plant.
Graft Versus Host Disease (GVHD) A side effect of a bone marrow or stem cell transplant that occurs when new bone marrow or stem cells (the graft) reject or attack the patient's body (the…
graft-versus-host disease (... dih-ZEEZ) A disease caused when cells from a donated stem cell graft attack the normal tissue of the transplant patient.
grafting The process of making a graft (1).
Grain Alcohol Ethanol.
Gram staining A technique to distinguish between two major bacterial groups, based on whether or not their cell wall retains the Gram stain.
Graminoid herbaceous A grass or plant of similar growth form, such as sedges, rushes, and others.
Grandfathered rights In Arizona, grandfathered water rights are based on historic use of groundwater for five years prior to the designation of an Active Management Area.
Granite A coarse-grained felsic intrusive (or plutonic) igneous rock with at least 65% silica.
Granitic General term for all light-colored, granite-like igneous rocks.
Granodiorite Coarse-grained intrusive igneous rock with less quartz and more feldspar than true granite and typically darker.
Granodiorites A plutonic igneous rock, formed by an intrusion of silica-rich magma, which cools in batholiths or stocks below the Earth's surface.
Granulation In solar-terrestrial terms, the cellular structure of the photosphere visible at high spatial resolution.
Granules Short-lived cells of plasma that carry heat to the Sun’s surface via convection (rising and falling).
Granulocyte (GRAN-yoo-loh-SITE) A type of white blood cell that fights bacterial infection. Neutrophils, eosinophils, and basophils are granulocytes.
Granulose cells Cells surrounding and maintaining the ovarian follicle.
granum (pl.: grana) Structure within the chloroplasts, appear as green granules with the light microscope and as a series of parallel lamellae with the electron…
Graphic Information Systems (GIS) GIS technology is used to develop maps that depict resources or features such as soil types, population densities, land uses, transportation corridors…
Grapple A clamshell-type bucket having three or more jaws.
GRAS Abbreviation for generally regarded as safe.
Grassland Terrestrial ecosystem (biome) found in regions where moderate annual average precipitation (25 to 76 centimeters or 10 to 30 inches) is enough to support…
Grasslands Grasslands are characterized as lands dominated by grasses rather than large shrubs or trees.
gratuitous inducer A substance that can induce transcription of a gene or genes, but is not a substrate for the induced enzyme(s).
Graupel Same as snow pellets or small hail.
Gravel Loose rounded fragments of rock that will pass a 3-inch sieve and be retained on a No. 4 U.S. Standard sieve (3/16 inch).
Gravel blanket Thin layer of gravel spread over an area either of natural ground, excavated surface, or embankment.
Gravel surfacing Layer of gravel spread over an area intended for vehicular or personnel traffic, such as roads, parking lots and sidewalks.
Gravelfill Gravel used to fill holes or spaces.
Graver A small tool with a sharp tip that was used to engrave bone, stone, wood, or other materials.
Gravitational Attraction The interaction of particles due to their mass/energy.
gravitropism See: geotropism.
Gravity arch dam A dam designed to combine load resisting features of both a gravity and arch type dam.
Gravity Dam A dam constructed of concrete and/or masonry which relies on its weight and internal strength for stability.
Gravity irrigation Irrigation method that applies irrigation water to fields by letting it flow from a higher level supply canal through ditches or furrows to fields at a…
Gravity Wave A wave created by the action of gravity on density variations in the stratified atmosphere.