Mendel performed numerous controlled genetic crosses to obtain strains that consistently produced a single phenotype without variation. what are these strains that consistently produce the same phenotype called?

True breeding strain

Explanation:

True breeding organism transfers their certain traits or characteristics in their all offspring. The true-breeding offspring appears to be identical in all ways. They respond to the environment in the same way.

They are homogeneous and their characteristics are responsible that differentiate between one member to another member of a species. There are many examples of true breeding such as animals, plants. Many of the breeder who wants to create a true-breeding strain. There are a few techniques that have been used in true strain breeding.  

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