Pure-bred

Pure-bred organisms are homozygous for the desired characteristics that a breeder wants. The offspring of a pure bred organism will always show the desired phenotype. The type is often got by inbreeding. Standard laboratory white rats are so genetically similar that they will accept skin grafts from other rats of the type. See strain (biology) for a fuller discussion.

This short article about biology can be made longer. You can help Wikipedia by adding to it.