Question

In Mendelian dihybrid cross for seed shape and seed colour, what percent of seeds produced in $F_2$ generation have only one recessive allele in the cells either for seed shape or for seed colour?
[0.7 mark]

• A. 50%
• B. 25%
• C. 33.33%
• D. 12.5%
  

Answer 1

The correct option is B 25%

In Mendelian dihybrid cross, out of sixteen individuals in $F_2$ generation, four have only one recessive allele that are two RrYY and two RRYy. Therefore, percentage of such individuals
$=\frac{4}{16}\times 100=25$