Law of Segregation

• Each true-breeding plant of the P generation has two identical alleles, denoted as either PP or pp.
• Gametes each contain only one allele for the corresponding gene, such as the flower color gene.
• The union of parental gametes produces F₁ hybrids having a Pp combination.
• During gamete formation of hybrid plants, the two alleles segregate.
• A Punnett Square shows all possible combinations of alleles in offspring that result from a cross between two F₁ hybrid plants (Pp x Pp).
• Each square in a Punnett Square represents an equally probable product of fertilization.
• Random combination of gametes results in a 3:1 ratio that Mendel observed in the F₂ generation.