Question

A cross was carried out between a pure bred tall pea plant and a pure bred dwarf pea plant and F 1 progeny was obtained . later , the F 1 progeny was self crossed to obtain F 2 progeny . ANSWER THE FOLLOWING QUESTIONS :

1) what is the phenotype of the F 1 progeny ?
2) give the Phenotypic ratio of the F 1 progeny .
3) why is the F 2 progeny different from the F 1 progeny ?

Answer 1

1) Phenotype of F1 Gen: Tall

2) Phenotypic Ratio - 1:2:1

3) In the F2 progeny, atleast 1/4 of the plants will be dwarfs due to the expression of the recessive allele whereas in the F1 progeny, all the plans will be tall.

Answer 2

1) In the F1 generation all tall plants occur so there will be no ratio

2)same as first

3) In the F1 generation only tall pea plant occur and in the F2 generation the tall pea plant occur three and dearf one

The ratio will become of F2 generation is 3:1