Answer:
selective breeding
Explanation:
Artificial selection is also known as selective breeding. Selective breeding refers to the process of breeding plants or animals selectively.
Thyroxine is an important hormone released into the bloodstream by the thyroid gland in the body. When tyroxine is released into the blood stream, it moves through certain organs such as the kidney and liver, where most of it is changed to an active form known as triiodothyronine. Thyroxine perform important roles in brain development, heart and digestive functions, bone maintenance, controlling muscle and metabolic rate of the body.
If the purple plant was homozygous dominate then it can only pass along a dominate allele to its offspring so despite the genotype of the other parent 100% of the offspring will reprsent a purple phenotype.