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Inbred Strains
Inbred strains (also called inbred lines, or rarely for animals linear animals) are individuals of a particular species which are nearly identical to each other in genotype due to long inbreeding. A strain is inbred when it has undergone at least 20 generations of brother x sister or offspring x parent mating, at which point at least 98.6% of the loci in an individual of the strain will be homozygous, and each individual can be treated effectively as clones. Some inbred strains have been bred for over 150 generations, leaving individuals in the population to be isogenic in nature. Inbred strains of animals are frequently used in laboratories for experiments where for the reproducibility of conclusions all the test animals should be as similar as possible. However, for some experiments, genetic diversity in the test population may be desired. Thus outbred strains of most laboratory animals are also available, where an outbred strain is a strain of an organism that is effectively wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
