Answer to Question #243363 in Genetics for Khangwelo Lovers

Question

In a particular species of plant, tall is dominant to short, and orange petals are dominant to the recessive white colour. Use T and t to symbolize the alleles for height, and F and f to symbolize the alleles for flower colour. A homozygous tall white flower is crossed with a flower heterozygous for both traits.

1.1 List the genotypes of the parents.

1.2 What are the F1 GENOTYPIC and PHENOTYPIC ratios?

1.3 What are the F2 genotypic and phenotypic ratios?

Answer 1

1.1 The parents genotypes are

TTff x TtFf

1.2 The F1 genotype will be

TTFf, TTff, TtFf, Ttff

The phenotypic ratio of tall and orange colored is $\frac{4}{8}=\frac{1}{2}$

The phenotypic ratio for tall and white is $\frac{4}{8}=\frac{1}{2}$

The genotypic ratio for each is $\frac{1}{4}$

1.3 The F2 genotypic and phenotypic will be

The phenotypic ratio of tall and orange colored is $\frac{4}{8}=\frac{1}{2}$

The phenotypic ratio for tall and white is $\frac{4}{8}=\frac{1}{2}$

The genotypic ratio for each is $\frac{3}{4}$