Problem 10: Disappearance of parental phenotypes in the F1 generationA genetic cross of inbred snapdragons with red flowers with inbred snapdragons with white flowers resulted in F1-hybrid offspring that all had pink flowers. When the F1 plants were self-pollinated, the resulting F2-generation plants had a phenotypic ratio of 1 red: 2 pink: 1 white. The most likely explanation is:TutorialIncomplete dominanceThe F1-hybrid plants have a different phenotype (pink flowers) than either of the true-breeding parents. This is an example of incomplete dominance. When the F1-hybrid plants are self-fertilized, both parental phenotypes (red flowered plants and white flowered plants) reappear in the F2 generation. The Biology Project Show
http://www.biology.arizona.edu Solution : In Snapdragon when two types of pure breeding plants bearing red flower and white flower are crossed the `F_1` generation plants neither bear red nor while lower but beat pink flower exhibiting the incomplete dominance. The self breeding of pink flowering plants yields a progeny consisting of three types of plants: red. pink and white i.e.. 1 :2:1 both phenotypically and genotypically Science grade 9 lm from Kris Ann Mae Yap Bonilla When the F2 phenotypic and genotypic ratios are same it is a case of?Thus, the correct answer is 'Incomplete dominance'.
Why are the genotypic and phenotypic ratios the same?But in the case of incomplete dominance, a monohybrid cross shows the result as in the above figure. Here, the genotypic and phenotypic ratios are the same. So, we can conclude that when genotypic and phenotypic ratios are the same, the alleles show incomplete dominance.
How is phenotypic and genotypic ratio same in this cross?In incomplete dominance and co-dominance, genotypic and phenotypic ratios are identical.
When F2 phenotypic as well as genotypic ratio are same in a cross then this cross shows?Final answer: F2 generation in a Mendelian cross with both genotypic and phenotypic ratios 1 : 2 : 1 is a case of incomplete dominance.
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