[Campbell Biology P.328] In snapdragons, the F1 generation from a cross between a red-flower... | Practice Question

In snapdragons, the F1 generation from a cross between a red-flowered plant CRCR and a white-flowered plant CWCW has pink flowers. What is the phenotypic ratio when these F1 hybrids are interbred?

  • A: 3 red : 1 white
  • B: 1 red : 2 pink : 1 white
  • C: All pink
  • D: 1 red : 1 white

Explanation

The text and Figure 14.10 show that for incomplete dominance, the F2 generation has a phenotypic ratio of 1 red CRCR : 2 pink CRCW : 1 white CWCW . This is because the heterozygote has a distinct, intermediate phenotype.