Question

Differentiate between monohybrid and dihybrid across

Answer 1

$<b ><i >$ Mendel defined two types of crosses:

1) Mono-hybrid Cross

A mono-hybrid cross is the cross between two homozygous parents (F1 generation) which differ in only one trait resulting in the second generation (F2 generation). This type of genetic cross yields a phenotypic ratio of 3:1. Thus, Mendel concluded that the F2 generation consists of 75% of organisms have a dominant phenotype out of which two-third are heterozygous while only 25 % of organisms have a recessive phenotype. For example crossing a tall pea plant with a short pea plant is a mono-hybrid cross.



2) Di-hybrid Cross

Di-hybrid cross is a cross between two heterozygous parents (F1 generation) which differ in two traits resulting in the second generation (F2 generation). In this type of cross, the genes are located on separate chromosomes. This type of genetic cross yields a phenotypic ratio of 9:3:3:1. Thus, Mendel concluded that the pair of traits passes on from one generation to another being independent of each other. For example crossing tall round pea plant with short wrinkled peas is a di-hybrid cross.