Question

How many plants are dihybrid in F${}_2$ generation of dihybrid cross?

• A. One
• B. Two
• C. Four
• D. Sixteen

Answer 1

The correct option is C Four

Dihybrid cross is a cross between two pure lines (varieties, strains) of that differ in two traits, i.e., allele pairs of particular interest. In Mendelian sense, between the alleles of both these loci, there is a relationship of complete dominance - recessive.
For example, RRYY/rryy parents result in F${}_1$ offspring that are heterozygous for both R and Y (RrYy).
It will yield 4 dihybrid plants in F${}_2$ generation. The ratio will be 9:3:3:1.
Hence, option C is correct.