Mendel’s experiments enabled him to formulate the law of segregation. This law has held up over time, although today we call Mendel’s “elements” alleles. Mendel’s law of segregation states that when an organism produces gametes, the two alleles for any given trait separate so that each gamete receives only one allele. Consequently, each parent donates only one of any two alleles to any offspring. The alleles don’t blend, but remain as discrete pieces of information as they pass from one generation to the next.