Conditions where only mutant or recombinant cells with a particular phenotype grow and divide.
A means of obtaining a clone containing a desired recombinant DNA molecule.
Differential and non-random reproduction of different genotypes, operating to alter the gene frequencies within a population.
In our case, we are using the characteristics of the recombinant plasmid (resistance to kanamycin and ampicillin) to find only those bacteria which contain that type of plasmid. By plating cells on media containing both antibiotics, we are selecting cells which meet these criteria. This type of selection is an artificial selection, imposed by the plates we make. Artificial selection is used by plant and animal breeders who want to develop strains of organisms with certain traits. Selection is a common tool of geneticists.
1. The process by which certain organisms are reproduced and perpetuated in the species in preference to others. Natural s. - the differential survival and reproduction of organisms with genetic characteristics that enable them to better use environmental resources. Artificial s. - the selective breeding by humans towards a desired trait in a plant, animal, or other organism which is of value (usually economic) to the humans. 2. Genetic breeding methods start by selecting particular desirable phenotypes as parents for the next generation.
Factors that affect the composition of the populations studied so as to confuse comparisons between groups, that is, produce artifactual findings.
Differential reproduction within a population that is correlated with the genotypes of individuals.
A change in allele frequency over time in a population.
A cell culture method that enables cells with specific characteristics to be isolated from a mixture of cells. For example, only cells that have incorporated a vector that encodes an antibiotic resistance gene would survive the addition of the antibiotic
The process that determines which individuals become parents, how many offspring they may produce, and how long they remain in the breeding population.
Causing or allowing certain individuals in a population to produce offspring in the next generation.
process in which bacteria with antibiotic resistance survive and multiply
the process in nature whereby one genotype leaves more offspring than another genotype because of superior life history attributes such as survival or fecundity
Natural or artificial process that results or tends to result in the survival and propagation of some individuals or organisms but not of others, with the result that the inherited traits of the survivors are perpetuated. In breeding, the directed procedure of picking certain seeds or animals for reproduction in order to influence the traits inherited by the next generation.
The process of determining the relative share allotted individuals of different genotypes in the propagation of a population; the selective effect of a gene can be defined by the probability that carriers of the gene will reproduce.
The process of saving the seeds from plants that exhibit desirable charac teristics and traits. To identify desirable characteristics, plant the same variety in different environmental conditions or plant different varieties in the same environ mental conditions.
describes the use of particular conditions to allow survival only of cells with a particular phenotype.
Differential and non-random reproduction of different genotypes within a population, often leading to a change in gene or genotype frequencies across generations.
Selection is present when a group selected from a larger population is not typical of the group as a whole eg the mortality rates for the group may be different. There are five types of selection studied in actuarial work: temporary initial selection, class selection, self selection, time selection and spurious selection.
In the context of evolution, certain traits or alleles of a species may be subject to selection. Under selection, individuals with advantageous or "adaptive" traits tend to be more successful than their peers reproductively--meaning they contribute more offspring to the succeeding generation than others do. When these traits have a genetic basis, selection can increase the prevalence of those traits, because offspring will inherit those traits from their parents.
Selection is the stage of a genetic algorithm in which individual genomes are chosen from a population for later breeding (recombination or crossover).