Question

In a dihybrid cross AABB $\times$ aabb, $F_2$ progeny of AABB, AABb, AaBB and AaBb occurs in the ratio of

• A. 1 : 1 : 1 : 1
• B. 9 : 3 : 3 : 1
• C. 1 : 2 : 2 : 1
• D. 1 : 2 : 2 : 4

Answer 1

The correct option is D 1 : 2 : 2 : 4

When a cross is made between AABB x aabb. In the F2 generation the genotypic ratio is AABB – 1 AABb – 2 AaBB – 2, AaBb – 4 AAbb – 1, Aabb – 2, aaBB – 1,aaBb – 2 aabb – 1.

So, the correct option is ‘1:2:2:4’.