Question

(i) State Mendel’s law of Independent Assortment. 

(ii) A homozygous Tall plant (T) bearing red coloured (R) flowers Amniotic Fluid is crossed with a homozygous Dwarf plant (t) bearing white flowers (r): 

(1) Give the Genotype and Phenotype of the F₁ generation. 

(2) Give the possible combinations of the gametes that can be obtained from the F₁ hybrid. 

(3) Give the dihybrid ratio and the phenotype of the offsprings of the F₂ generation when two plants of the F₁ generation above are crossed.

Answer 1

(i) Mendel’s law of Independent Assortment: When there are two pairs of contrasting characters, the distribution of the members of one pair into the gametes is independent of the distribution of the other pair. 

(ii) (1) Genotype of the F₁ generation – TtRr, Phenotype of the F₁ generation – Tall plant and Red flower. 

(2) Possible combination of the gametes from F₁ hybrid: TR, Tr, tR, tr. 

(3) Dihybrid ratio and phenotype of the F₂ generation: