| tandem repeat sequence | <molecular biology> Multiple copies of the same base sequence on a chromosome, used as a marker in physical mapping. (09 Oct 1997) |
|---|---|
| termination sequence | <molecular biology> The three codons, UAA known as ochre, UAG as amber and UGA as opal, that do not code for an amino acid but act as signals for the termination of protein synthesis. They are not represented by any tRNA and termination is catalysed by protein release factors. There are two release factors in E. Coli, RF1 recognises UAA and UAG, RF2 recognises UAA and UGA. Eukaryotes have a single GTP requiring factor, eRF. See: ochre suppressor, amber suppressor. (13 Jan 1998) |
| enhancer sequence | <molecular biology> A nucleotide sequence, located as many as several thousand base pairs away in either direction from the target gene, which enhances transcription of that gene. (14 Nov 1997) |
| evolutionarily conserved sequence | A base sequence in a DNA molecule (or an amino acid sequence in a protein) that has remained essentially unchanged throughout evolution. (12 Dec 1998) |
| Expressed Sequence Tag | <molecular biology> Expressed sequence tags are sequence tagged sites derived from cDNAs. See: sequence tagged site. Acronym: EST (06 Aug 1998) |
| flanking sequence | <molecular biology> Short DNA sequences bordering a transcription unit. Often these do not code for proteins. (18 Nov 1997) |
| leader sequence | <molecular biology> In the regulation of gene expression for enzymes concerned with amino acid synthesis in prokaryotes, the leader sequence codes for the leader peptide that contains several residues of the amino acid being regulated. Transcription is closely linked to translation and if translation is retarded by limited supply of amino acyl tRNA for the specific amino acid, the mode of transcription of the leader sequence permits full transcription of the operon genes, otherwise complete transcription of the leader sequence prematurely terminates transcription of the operon. (18 Nov 1997) |
| accumulation analysis | A technique in which an intermediate of a metabolic pathway accumulates due to selective inhibition of a particular step in that pathway or in a mutant that is deficient in a certain step. The intermediate is then isolated, analyzed, and identified. (05 Mar 2000) |
| activation analysis | <radiobiology> Method for identifying and measuring chemical elements in a sample of material. Sample is first made radioactive by bombardment with neutrons, charged particles, or gamma rays. Newly formed radioactive atoms in the sample then give off characteristic radiations (such as gamma rays) that tell what kinds of atoms are present, and how many. (09 Oct 1997) |
| actuarial analysis | The application of probability and statistical methods to calculate the risk of occurrence of any event, such as onset of illness, recurrent disease, hospitalization, disability, or death. It may include calculation of the anticipated money costs of such events and of the premiums necessary to provide for payment of such costs. (12 Dec 1998) |
| amino acid analysis | Determination and identification of amino acid content of a macromolecule, identification of a specific amino acid in macromolecules, often a mutated protein, identification and quantitation of amino acid content in blood plasma or urine; a key diagnostic aid. (05 Mar 2000) |
| analysis | <technique> The separation into component parts or elements, the act of determining the component parts of a substance. Origin: Gr. Lysis = dissolution (18 Nov 1997) |
| analysis of variance | A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable. (12 Dec 1998) |
| bite analysis | A study of the relations of the occlusal surfaces of opposing teeth and their effect upon related structures. Synonym: bite analysis. (05 Mar 2000) |
| blood gas analysis | <investigation> A test which analyses arterial blood for oxygen, carbon dioxide and bicarbonate content in addition to blood pH. Used to test the effectiveness of respiration. (27 Sep 1997) |