| mitotic cell selection | A drug-free procedure for the selection of mitotic cells from an exponentially growing monolayer. (09 Oct 1997) |
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| selection | <biology> Placing organisms under conditions where the growth of those with a particular genotype will be favored. (09 Oct 1997) |
| selection bias | The introduction of error due to systematic differences in the characteristics between those selected and those not selected for a given study. In sampling bias, error is the result of failure to ensure that all members of the reference population have a known chance of selection in the sample. (12 Dec 1998) |
| selection coefficient | The proportion of progeny or potential progeny not surviving to sexual maturity; usually defined artificially by expressing the fitness of a phenotype as a fraction of the mean or optimal fitness to give the relative fitness, and subtracting this fraction from unity. If the mean size of family in the population is 3.2 and that for a particular genotype is 2.4 then the fitness of the phenotype is 2.4/3.2 =0.75 and the selection coefficient =1-0.75 =.25 = 5 (05 Mar 2000) |
| selection cutting | The periodic removal at short intervals of the oldest and largest trees in the stand, individually or in small groups. (05 Dec 1998) |
| selection (genetics) | Differential and non-random reproduction of different genotypes, operating to alter the gene frequencies within a population. (12 Dec 1998) |
| selection pressure | Impact of effective reproduction due to environmental impact on the phenotype. (05 Mar 2000) |
| sexual selection | A form of natural selection in which, according to Darwin's theory, the male or female is attracted by certain characteristics, form, colour, behaviour, etc., in the opposite sex; thus modifications of a special nature are brought about in the species. (05 Mar 2000) |
| natural selection | The hypothesis that genotype environment interactions occurring at the phenotypic level lead to differential reproductive success of individuals and hence to modification of the gene pool of a population. (18 Nov 1997) |
| insurance selection bias | Adverse of favourable selection bias exhibited by insurers or enrollees resulting in disproportionate enrollment of certain groups of people. (12 Dec 1998) |
| k selection | <zoology> In evolution, the selection of traits that aid an organisms competitive capability when the population is at or near its carrying capacity. (21 Mar 1998) |