Answer:
The law of segregation states that genes have alternative forms, or alleles. In a diploid organism, the two alleles of a gene separate during meiosis and gamete formation; each sperm or egg carries only one allele of each pair. This law explains the 3:1 ratio of the F2 phenotype observed when monohybrids self-pollinate. Each organism inherits one allele for each gene from the parent. In heterozygous individuals, the two alleles are different, and expression of the dominant allele masks the phenotypic effect of the recessive allele. In hom0zygous individuals, the two alleles are identical.
The law of independent assortment states that the pair of alleles for a given gene segregates into gametes independently of the pair of alleles for any other gene. This law explains the 9:3:3:1 ratio of the F2 phenotypes in a cross between dihybrids.
Step-by-step explanation:
The law of segregation explains that, during gamete formation, each gamete receives just one copy of the gene (allele) which is random. Therefore, if we have two heterozygotes (Aa), the possible genotypes are AA, aa, Aa and Aa. Therefore, the ratio of the dominant phenotype to the recessive is 3:1.
The law of independent assortment explains that the alleles of different genes are inherited independently of one another. That explains the 9:3:3:1 phenotype ratio when crossing two individuals heterozygous at two different genes