We want to cross our alleles between this genotype and this genotype here. So let's suppose this column are the alleles that came from this parent. So we have upper case T, lower case T. Remember, the law of segregation tells us that during the process of meiosis, when we actually form the sex cell dirtyamides, we have the separation of these homologous chromosomes. And so the separation of these two genes, these two alleles. So we have uppercase T goes into this gamete, and we have the lowercase T goes into this gamete. And the same thing is true for our genotype T lowercase T, lowercase T. Now we actually cross them.