Mendel's law of ______ states that alternative versions of genes are packaged into separate gametes.

Mendel's law of segregation states that alternative versions of genes, known as alleles, are packaged into separate gametes during the formation of reproductive cells. This means that an individual inherits two alleles for each trait, one from each parent, but these alleles are separated during gamete formation so that each gamete contains only one allele for each trait.

This principle was formulated by Gregor Mendel in the 19th century based on his experiments with pea plants. It underlies the concept of inheritance, describing how traits are passed from parents to offspring. Mendel's law of segregation helps explain the genetic variability observed in living organisms, as each gamete contributes a unique combination of alleles, leading to genetically diverse offspring.