wrinkled seeds (rr), yellow cotyledon (YY) was dominant over green cotyledon (yy). What are the expected phenotypes in the
F₂-generation of the cross RRYY X rryy?
(a) Only round seeds with green cotyledons
(b) Only wrinkled seeds with yellow cotyledons
(c) Only wrinkled seeds with green cotyledons
(d) Round seeds with yellow cotyledons and wrinkled seeds with yellow cotyledons
[CBSE AIPMT 2006]
Correct Option (d) Reason : When a cross (dihybrid) is made between plants bearing round yellow (RRYY) and wrinkled green (rryy) seeds, all the plants in F₁-generation are with
yellow round seeds (showing the genotype RrYy). The phenotype in F₂ will be as follows