Food Biotechnology — page 11 of 34

Food Biotechnology terms

1001. enhancer 1. A substance or object that increases a chemical activity or a physiological process. 2.
1002. enhancer element See: enhancer.
1003. enhancer sequence See: enhancer.
1004. enolpyruvyl-shikimate-3-phosphate synthase (Abbreviation EPSP synthase or EPSPS). An enzyme produced by virtually all plants, which is essential for normal metabolism, and for the biosynthesis of…
1005. enterotoxin A bacterial protein that, following release into the intestine, causes cramps, diarrhoea and nausea.
1006. Enucleated oocyte (cytoplast) An egg cell from which the nucleus has been removed mechanically.
1007. enucleated ovum Egg cell from which the nucleus has been removed, usually as a preparatory step for nuclear transfer.
1008. Environmental Protection Agency (EPA) (EPA) Environmental Protection Agency (EPA) was established as an independent agency on December 2, 1970 during President Nixon's term in office.
1009. enzyme A protein that speeds up chemical reactions in the body.
1010. enzyme bioreactor A reactor in which a chemical conversion reaction is catalysed by an enzyme.
1011. Enzyme Commission number (Abbreviation: EC number). Systematic label which identifies an enzyme in the technical literature.
1012. enzyme electrode A type of biosensor, in which an enzyme is immobilized onto the surface of an electrode.
1013. enzyme immunoassay A range of immunoassay techniques employing enzymes, which includes ELISA.
1014. enzyme kinetics The quantitative characteristics of enzyme reactions.
1015. enzyme stabilization Maintaining the active conformation of an enzyme. This can be achieved in vitro by providing the appropriate chemical environment and cofactors.
1016. enzyme-linked immunosorbent assay See: ELISA.
1017. Enzymes Proteins that control the various steps in all chemical reactions.
1018. EPA See Environmental Protection Agency.
1019. EPD See: expected progeny difference.
1020. epicotyl The upper portion of the axis of a plant embryo or seedling, above the cotyledons.
1021. epidermis (ep-i-DER-mis) The upper or outer layer of the two main layers of tissue that make up the skin.
1022. epigenesis Describes the developmental process whereby each successive stage of normal development is built up on the foundations created by the preceding stages of…
1023. epigenetic variation Non-hereditary and reversible variation; often the result of a change in gene expression due to methylation of DNA.
1024. epinasty A process by which the growth of branches or petioles is abnormally pointing downward.
1025. epiphyte A plant that grows upon another plant, but is neither parasitic on it nor rooted in the ground.
1026. episome A genetic extrachromosomal element (e.g. the F factor in Escherichia coli) which replicates within a cell independently of the chromosome and is able to…
1027. Epistasis Interaction between genes at different loci, e.g. one gene suppresses the effect of another gene that is situated at a different locus.
1028. epitope (EP-i-tope) A part of a molecule that an antibody will recognize and bind to.
1029. epizootic A disease simultaneously affecting a large number of animals.
1030. EPSP synthase Abbreviation for enolpyruvyl-shikimate 3-phosphate synthase.
1031. EPSPS Abbreviation for enolpyruvyl-shikimate 3-phosphate synthase.
1032. equational division A chromosome division in which the two chromatids of each duplicated chromosome separate longitudinally, prior to being incorporated into two daughter…
1033. equilibrium density gradient centrifugation A procedure used to separate macromolecules based on their density (mass per unit volume).
1034. ER Describes cells that do not have a protein to which the hormone estrogen will bind.
1035. Erlenmeyer flask A conical flat-bottomed laboratory flask with a narrow neck, widely used for culturing micro-organisms.
1036. ES cells See: embryonic stem cells.
1037. Escherichia coli A commensal bacterium inhabiting the human colon that is widely used in biology, both as a simple model of cell biochemical function and as a host for…
1038. essential amino acid An amino acid required for normal metabolism, but which cannot be synthesized by an organism. It therefore has to be supplied via feed or food.
1039. essential derivation of varieties (Abbreviation: EDV). Genotypes very similar to an originating cultivar, obtained, for example, by the selection of a mutant or a variant individual from…
1040. Essential element Any of a number of elements required by living organisms to ensure normal growth, development and maintenance.
1041. essential nutrient Any substance required by living organisms to ensure normal growth, development and maintenance.
1042. essential requirement In plant cell tissue culture, comprises inorganic salts, including all of the elements necessary for plant metabolism; organic factors (amino acids…
1043. EST See: expressed sequence tag.
1044. established culture 1. An aseptic viable explant (See: micropropagation ). 2. A suspension culture subjected to several passages with a constant cell number per unit time.
1045. estimated breeding value (Abbreviation: EBV). Twice the expected progeny difference. The difference is doubled because breeding value is a reflection of all the genes of an…
1046. Estrogen A type of hormone made by the body that helps develop and maintain female sex characteristics and the growth of long bones.
1047. ET And; also.
1048. ethanol Commonly used to disinfect plant tissues, glassware utensils and working surfaces in tissue culture manipulations; to precipitate aqueous solutions of…
1049. ethephon A synthetic compound commonly used as a source of ethylene, a gaseous plant growth regulator.
1050. Ethidium bromide A fluorescent dye used to stain DNA and RNA. The dye fluoresces when exposed to UV light.
1051. ethyl alcohol See: ethanol.
1052. ethylene A gaseous plant growth regulator acting on various aspects of vegetative growth, fruit ripening and abscission of plant parts. Synonym: ethene.
1053. ethylenediamine tetraacetic acid (Abbreviation: EDTA). A chelating compound. Used to keep nutrients, such as iron, bound in a soluble form that leaves them still available to the plant…
1054. etiolation An abnormal increase in stem elongation, accompanied by poor (if any) leaf development.
1055. ETL See: economic trait locus.
1056. eucaryote See: eukaryote.
1057. eucaryotic (adj.) See: eukaryote.
1058. euchromatin Chromosomal material that is stained less intensely by certain dyes. Thought to be the chromosomal domains which are gene-rich, since the DNA in these…
1059. Eugenics The application of the principles of genetics to the 'improvement' of humankind. Wholly discredited as a scientific approach since the Nazi period.
1060. Eukaryote An organism whose cells possess a nucleus and other membrane-bound vesicles, including all members of the protist, fungi, plant and animal kingdoms; and…
1061. euploid An organism or cell having a chromosome number that is an exact multiple of the haploid number.
1062. Evapotranspiration The net water loss (in vapour form) per unit area of land, both directly from the land surface, and indirectly through transpiring leaves.
1063. Evolution Changing with time.
1064. ex vitro Organisms removed from tissue culture and transplanted; generally plants to soil or potting mixture.
1065. ex vivo gene therapy The delivery of a gene or genes to the isolated cells of an individual, with the intention of alleviating a genetic disorder.
1066. ex-situ conservation The conservation of components of biological diversity outside their natural habitats.
1067. excinuclease The endonuclease -containing protein complex that excises a segment of damaged DNA during excision repair.
1068. excision (ek-SIH-zhun) Removal by surgery.
1069. excision repair DNA repair processes that involve the removal of a damaged or incorrect segment of one strand of double-stranded DNA and its replacement by the synthesis of a…
1070. excitation wavelength The specific wavelength of light required to stimulate a fluorescent molecule, such as a labelled probe, to emit light at the (lower) emission wavelength.
1071. excrete (ek-SKREET) To get rid of waste material from the blood, tissues, or organs by a normal discharge (such as sweat, urine, or stool).
1072. exit site (Abbreviation: E site). The ribosome binding site that contains the free tRNA prior to its release.
1073. exo III See: exonuclease III.
1074. exocrine gland An animal gland that secretes through a duct.
1075. exodeoxyribonuclease III See: exonuclease III.
1076. exogamy See: outbreeding.
1077. exogenous Produced outside of; originating from, or due to, external causes. Opposite: endogenous.
1078. Exogenous DNA DNA that has been derived from one organism, and is to be introduced into a cell a different species. Also referred to as foreign DNA or heterologous DNA.
1079. Exon A DNA sequence that is ultimately translated into protein. See DNA.
1080. exon amplification A procedure that is used to amplify exons.
1081. Exonuclease See Nuclease.
1082. exonuclease III (Abbreviation: exo III). An Escherichia coli enzyme that removes nucleotides from the 3' hydroxyl ends of double-stranded DNA.
1083. exopolysaccharide A polysaccharide that is secreted by a micro-organism into the surrounding environment.
1084. exotoxin A toxin released by a bacterium into the medium in which it grows.
1085. expected progeny difference (Abbreviation: EPD). The predicted performance of the future offspring of an individual for a particular trait, calculated from measurement(s) of the…
1086. explant A portion of a plant aseptically excised and prepared for culture in a nutrient medium.
1087. explant donor The plant from which an explant has been taken.
1088. explantation The removal of cells, tissues or organs of animals and plants for observation of their growth and development in appropriate culture media.
1089. explosion method A technique for the genetic transformation of cells, in which the transgene is driven into the target (plant) cells by the sudden vaporization (effected…
1090. exponential phase See: logarithmic phase.
1091. export Data extracted or taken out of one environment or application usually in a prescribed format, and usually for import into another environment or…
1092. Express To translate a gene's message into a molecular product.
1093. expressed sequence tag (Abbreviation: EST). Partially sequenced cDNA clone. Because the read length of a standard DNA sequencing reaction is shorter than the majority of cDNA…
1094. Expression library (See Library.)
1095. expression system Combination of host and vector which provides a genetic context for making a cloned gene functional, i.e. produce peptide, in the host cell.
1096. expression vector A cloning vector that has been constructed in such a way that, after insertion of a DNA molecule, its coding sequence is properly transcribed and the mRNA…
1097. expressivity Degree of expression of a trait controlled by a particular gene. The gene may show different degrees of expression in different individuals.
1098. extension The short single-stranded stretch of nucleotides remaining on a double-stranded DNA molecule, following treatment with a restriction endonuclease which…
1099. external guide sequence (Abbreviation: EGS). See: guide sequence.
1100. extrachromosomal In eukaryotes, non-nuclear DNA, present in cytoplasm organelles such as mitochondria and chloroplasts . In prokaryotes, non-chromosomal DNA, i.e. plasmids.