Question

Explain dihybrid cross with proper diagram.
​

Answer 1

Answer:

Dihybrid cross : When cross between two varieties having two contrasting characters takes place, then it is called dihybrid cross. In R generation, on the basis of law of dominance only dominant characters appear. During gamete formation, genes of contrasting characters separate and only one enters each gene. On self fertilization, the F generation develops a generation in which there appears 9:3:3:1 phenotypic ratio. In generation, new combinations also develops.

Answer 2

A dihybrid cross describes a mating experiment between two organisms that are identically hybrid for two traits. A hybrid organism is one that is heterozygous, which means that carries two different alleles at a particular genetic position or locus.

In a dihybrid cross, Mendel took a pair of contradicting traits together for crossing; for example color and the shape of seeds at a time. He picked the wrinkled-green seed and round-yellow seed and crossed them. He obtained only round-yellow seeds in the F1 generation. This indicated that round shape and yellow color of seeds are dominant in nature. While the wrinkled shape and green color of seeds are recessive traits. Then, F1 progeny was self-pollinated. This resulted in four different combinations of seeds in F2 generation. They were wrinkled-yellow, round-yellow, wrinkled-green seeds and round-green in the phenotypic ratio of 9:3:3:1.