The expected ratio from a dihybrid cross between two double heterozygotes (unlinked genes) is

  1. 9 : 3 : 3 : 1
  2. 3 : 1
  3. 1 : 1 : 1 : 1
  4. 1 : 2 : 1
Answer

A) 9 : 3 : 3 : 1

AaBb × AaBb. AS & A Level Biology · Topic 16 Inheritance · 16.2 The roles of genes in determining the phenotype

Biology MCQ · More A Level Biology: Inheritance MCQs · Practise