Answer:
True breeding
Explanation:
One of the main reasons behind the success of Mendel's experiments was that he started the experiments with pea varieties that were true breeding. It is important to understand what a true breeding variety is, it is a plant or organism that is homozygous for a certain trait, in Mendel's case, the pea varieties were homozygous for seven traits, which are : seed coat tint, pod shape, seed shape, flower color, flower location, unripe pod color, and plant height. It means that the varieties contained two similar alleles of genes for these traits in pea plant varieties he chose. Due to the true breeding nature of these traits, the parent plants produced offspring that showed the phenotype just like their parents.
For example:
Here is a cross between plant with yellow flower with another plant containing yellow flower.Suppose allele for yellow is Y and allele for green is y. Let us see what happens in this breeding:
Parents: YY X YY
Offspring: YY
Again cross between offspring: YY X YY
Offspring: YY
This is true breeding in which offspring contain phenotype of parent in many successive generations.
Hope it helps!
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