Question

In $F_2$ generation quantitative inheritance of 1 : 4 : 6 : 4 : 1 is obtained instead of

• A. 9 : 3 : 3 : 1
• B. 8 : 6 : 4 : 1
• C. 7 : 4 : 1 : 4
• D. 6 : 6 : 4 : 7

Answer 1

The correct option is A 9 : 3 : 3 : 1

Inheritance is controlled by two or more genes in which the dominant alleles have cumulative effect, with each dominant allele expressing a part of functional polypeptide and full trait is shown when all the dominant alleles are present, is called Polygenic or Quantitative inheritance. A red kernel variety of wheat is crossed white kernel variety of wheat. The grains of F1 were uniformly red but intermediate between the red and white of parental generations. When the F1 members were self crossed among themselves, five different phenotypic classes appeared in F2 showing the ratio of 1:4:6:4:1 instead of Mendel’s 9:3:3:1.

So, the correct option is ‘9:3:3:1’.