Answer:
Law of segregation and independent assortment
Step-by-step explanation:
The alleles of a gene on the chromosomes of the cell have an equal chance of ending up in any one of the gametes formed during gamete formation. This is because the alleles remain separate on sister chromosomes and therefore separate and randomly end up in either of the gametes. Therefore in case of a heterozygous trait, some of the gametes will bear the recessive alelle while others will bear the dominant allele of the trait.