Home › UP Board Class 12 › biology › Principles of Inheritance and Variation › The phenotypic ratio in the F₂ of a Mendelian di…
The phenotypic ratio in the F₂ of a Mendelian dihybrid cross (with two independently assorting genes) is
A3 : 1
B1 : 2 : 1
C9 : 3 : 3 : 1
D1 : 1 : 1 : 1
Answer & Solution
Correct answer: C. 9 : 3 : 3 : 1
The dihybrid F₂ ratio 9:3:3:1 follows directly from two independent 3:1 monohybrid ratios. It also implies independent assortment — if the two genes were linked, the ratio would deviate.
Related questions
Haemophilia and colour blindness are MORE COMMON in MALES than females because they are:Down syndrome is most commonly caused by:Sickle cell anaemia is caused by:The sex of a human baby is determined by:In the human ABO blood group system, a person with blood group AB has the genotype:In snapdragon (Antirrhinum), RR (red) × rr (white) gives F1 plants that are PINK. This patIn a DIHYBRID cross of YyRr × YyRr, the F2 phenotypic ratio is:In a monohybrid cross of Tt × Tt, the F2 PHENOTYPIC ratio is: