Question

a tall, purple - flowered pea plant (ttpp) is allowed to self - pollinate. (the recessive alleles code for short plants and white flowers.) the phenotypic ratio of the resulting offspring is 9:3:3:1. what is the genotype of the plant whose phenotype appeared once out of every 16 offspring (the \1\ in the 9:3:3:1 ratio)?
view available hint(s)
○ ttpp
○ ttpp
○ ttpp
○ ttpp

Explanation:

Step1: Analyze the 9:3:3:1 ratio

The 9:3:3:1 phenotypic ratio in a dihybrid cross (self - pollination of a plant with two heterozygous traits) indicates that the original plant is heterozygous for both traits. The given plant has the genotype TtPp (tall, purple - flowered). When it self - pollinates, the possible genotypes of the offspring are determined by the independent assortment of the T/t and P/p alleles.

Step2: Determine the "1" phenotype in 9:3:3:1

The "1" in the 9:3:3:1 ratio corresponds to the double - recessive phenotype, which is short (tt) and white - flowered (pp). So the genotype of the plant with this phenotype (appearing once in 16 offspring) is ttpp.

Answer:

ttpp