Question

Which cross yields red, white, and pink variety of dog flower?

• A. RR $\times$ Rr
• B. Rr $\times$ Rr
• C. Rr $\times$ RR
• D. Rr $\times$ rr

Answer 1

The correct option is B Rr $\times$ Rr

Dog flower is another name of Snapdragon (Antirrhinum majus). This is a case of incomplete dominance where heterozygous individuals show intermediate phenotypes. This is due to the intermediate level of gene expression, as neither allele is able to show complete dominance. In this case, selfing the heterozygous pair can yield three different phenotypes in the offspring i.e., red, white, and pink variety of dog flowers.