Question

A farmer cultivates a unique species of tomato plants. The two traits selected for breeding were: Colour of the fruits and height of the plants. The farmer initially crosses a homozygous tall plant bearing red fruits (TTRR) with a dwarf plant bearing yellow fruits (ttrr) and the genotype of all the offsprings of the F1 generation was TtRr. Next, he crosses two F1 generation plants (TtRr).

1. Explain the phenotype of the offsprings of the F₁ generation obtained from the initial cross.
2. Mention the phenotypic ratio of the F₂ generation offsprings
3. State Mendel’s Law of Independent Assortment.

Answer 1

1. Phenotype of offspring in F₁ generation are tall plants with red fruits.
2. 9 tall red : 3 tall yellow: 3 dwarf red :1 dwarf yellow
3. Law of Independent Assortment: It states that when two characters are present, the distribution of one’s alleles in gametes is not affected by the distribution of the other’s alleles.