Now, in experiment number one, what he did was he took a true breeding tall plant and he mixed it, he crossed it with a true breeding short plant. And what that basically means is he took a homozygous dominant plant and he mixed it with a homozygous recessive plant. So the phenotype for this plant is tall and the genotype is uppercase T. Uppercase T, where upper case T represents that gene that codes for proteins that expresses the tall height. Now, in the case of the homozygous recessive plan, we have a short phenotype and we have a genotype equaling to lowercase T, lowercase T, where lowercase T is the gene that codes for proteins that expresses the short trait and not the toll trait. Now, every time he conducted this same experiment, he always found that the f one generation offspring was always tall. It was never short.