IUPAC Glossary of Terms Used in Toxicology - Terms Starting with G

gamete
Reproductive cell (either sperm or egg) containing a haploid set of chromosomes.

gametocide
Substance intended to kill gametes.

gastroenteritis
Inflammation of the stomach and intestine.

gastrointestinal
Pertaining or communicating with the stomach and intestine.

gavage
Administration of materials directly into the stomach by esophageal intubation.

gene
Length of DNA that encodes a functional product, which may be a polypeptide or a ribonucleic acid.
Note: A gene is the fundamental unit of heredity
After [9]

gene amplification
Occurrence of extra copies of a gene; with respect to a plasmid, an increase in the number of plasmid copies per cell, which may be induced by a specific treatment.
Note: Spontaneous gene amplification frequently occurs in tumor cells.

gene expression
Transcriptional activation of a gene so that its functional product is produced.

gene therapy
Introduction of genetic material into an individual, or the modification of the individual’s genetic material, in order to achieve a therapeutic or prophylactic objective.
After [9]

genetic epidemiology
Study of the correlations between phenotypic trends and genetic variation across population groups and the application of the results of such a study to control of health problems.

gene map
Map showing the positions in the genome of genes or other genetic markers, either relative to each other or as a physical map of absolute distances.

generally regarded as safe (GRAS)
Phrase used to describe the U.S. FDA philosophy that justifies approval of food additives that may not meet the usual test criteria for safety but have been used extensively and have not demonstrated to cause any harm to consumers.

genetically modified organism (GMO)
Bacterium, plant or animal whose deoxyribonucleic acid has been deliberately altered.

genetic polymorphism
Existence of inter-individual differences in DNA sequences coding for one specific gene, giving rise to different functional and (or) morphological traits.
After [2]

genetic susceptibility
Predisposition to a particular disease or sensitivity to a substance due to the presence of a specific allele or combination of alleles in an individual’s genome.
After [9]

genetic toxicology
Study of chemically or physically induced changes to the structure of DNA, including epigenetic phenomena or mutations that may or may not be heritable.

genome
Complete set of chromosomal and extrachromosomal genes of an organism, a cell, an organelle, or a virus, i.e. the complete DNA component of an organism.
Note: This includes both the DNA present in the chromosomes and that in subcellular organelles (e.g. mitochondria or chloroplasts). It also includes the RNA genomes of some viruses.
[2]

1. Science of using DNA and RNA based technologies to demonstrate alterations in genes expression.
2. (in toxicology) Method providing information on the consequences for genes expression of interactions of the organism with environmental stress, xenobiotics, etc.
   [2]

genotoxic
Capable of causing a change to the structure of the genome.

genotype
Genetic constitution of an organism as revealed by genetic or molecular analysis; the complete set of genes possessed by a particular organism, cell, organelle or virus.

germ-free animal
axenic animal

Animal grown under sterile conditions in the period of postnatal development: such animals are usually obtained by Caesarean operation and kept in special sterile boxes in which there are no viable micro-organisms (sterile air, food and water are supplied).

germ-line cell
Cell with a haploid chromosome content.
Note: In animals, the germ-line cells are the sperm or egg (synonym gamete); in plants, the pollen cell or the ovum.
After [9]

germinal aplasia
Complete failure of gonad development.

germ warfare
See biological warfare

glomerular
Pertaining to a tuft or cluster, as of a plexus of capillary blood vessels or nerve fibers, especially referring to the capillaries of the glomerular of the kidney.

glomerulus
Tuft or a cluster, as of a plexus of capillary blood vessels or nerve fibers, e. g. capillaries of the filtration apparatus of the kidney.

glomerular filtration
Formation of an ultrafiltrate of the blood occurring in the glomerulus of the kidney.
[2]

glomerular filtration rate
Volume of ultrafiltrate formed in the kidney tubules from the blood passing through the glomerular capillaries divided by time of filtration.
[2]

“glue sniffing”
Solvent abuse using plastic cement or other solvent-based adhesives.

glycobiology
See glycomics

glycome
Description of the complete set of carbohydrates and their functions in a living organism.

glycomics
glycobiology
Global study of the structure and function of carbohydrates, especially oligosaccharides (short chains of sugars) in a living organism.

gnotobiont
See gnotobiote

gnotobiota
Specifically and entirely known microfauna and microflora of a specially reared laboratory animal.

gnotobiot/e n., -ic adj.
gnotobiont
Specially reared laboratory animal whose microflora and microfauna are specifically known in their entirety.

goiter
Noncancerous enlargement of the thyroid gland, visible as a swelling at the front of the neck, that is often associated with iodine deficiency.

goitrogen
Any substance (such as thiouracil) that induces the formation of a goiter.

gonadotropic
Pertaining to effects on sex glands and on the systems that regulate them.

good agricultural practice in the use of pesticides (GAP)
Nationally authorized safe uses of pesticides under actual conditions necessary for effective and reliable pest control.
Note: It encompasses a range of levels of pesticide applications up to the highest authorized use, applied in a manner that leaves a residue which is the smallest amount practicable. Authorized safe uses include nationally registered or recommended uses, that take into account public and occupational health and environmental safety considerations. Actual conditions include any stage in the production, storage, transport, distribution, and processing of food commodities and animal feed.

good laboratory practice principles (GLP)
Fundamental rules incorporated in OECD guidelines and national regulations concerned with the process of effective organization and the conditions under which laboratory studies are properly planned, performed, monitored, recorded, and reported.

good manufacturing practice principles (GMP)
Fundamental rules incorporated in national regulations concerned with the process of effective organization of production and ensuring standards of defined quality at all stages of production, distribution and marketing.
Note: Minimization of waste and its proper disposal are part of this process.

graded effect
antonyms all-or-none effect, quantal effect, stochastic effect
Consequence that can be measured on a graded scale of intensity or severity and its magnitude related directly to the dose or concentration of the substance producing it.

graminicide
Pesticide (herbicide) used for the control of weedy grasses (Gramineae).
[6]

granuloma
Granular growth or tumor, usually of lymphoid and epithelial cells.

ground treatment of plants
Dusting or spraying of plants with pesticides by hand, by special machines, or by apparatus fixed to tractors or driven by them.

guideline for exposure limits
Scientifically judged quantitative value (a concentration or number) of an environmental constituent that ensures aesthetically pleasing air, water or food and from which no adverse effect is expected concerning noncarcinogenic endpoints, or that gives an acceptably low estimate of lifetime cancer risk from those substances which are proven human carcinogens or carcinogens with at least limited evidence of human carcinogenicity.

guideline value
Quantitative measure (a concentration or a number) of a constituent of an environmental medium that ensures aesthetically pleasing air, water, or food and does not result in a significant risk to the user.

guides to air quality
Sets of atmospheric concentrations and exposure times that are associated with specific effects of varying degrees of pollution on man, animals, vegetation, and the environment in general.

guides to environmental quality
Sets of concentrations, numbers and exposure times that are associated with the specific effects of factors in environmental media on man, animals, vegetation, and the environment in general.

guinea-pig maximization test
Magnusson and Kligman test
Widely used skin test for screening possible contact allergens: considered to be a useful method to identify likely moderate and strong sensitizers in humans.