question_answer

Directions : (6 - 10)

Read the passage given below and answer the following questions.

Though the genotypic ratios can be calculated using mathematical probability, but simply looking at the phenotype of a dominant trait, it is not possible to know the genotypic composition. That is, for example, whether a tall plant from \[{{F}_{1}}\] or \[{{F}_{2}}\] has TT or Tt composition, cannot be predicted. Therefore, to determine the genotype of a tall plant at \[{{F}_{2}}\], Mendel crossed the tall plant from \[{{F}_{1}}\], with a dwarf plant i.e., recessive parent. This he called a test cross. In a typical test cross an organism like Pea plants showing a dominant phenotype and whose genotype is to be determined is crossed with the recessive parent instead of self-crossing or selfing. The progenies of such a cross can easily be analysed to predict the genotype of the test organism.

What ratio did you get during test cross of a Pea plant?

A) 1 : 2 : 1

B) 1 : 1

C) 3 : 1

D) 2 : 1