A cross was made between pure breeding pea plants one with round and green seeds and the other with wrinkled and yellow seeds.

(a) Write the phenotype of F1 progeny. Give reason for your answer.

(b) Write the different types of F2 progeny obtained along with their ration when F1 progeny was selfed.

(a) The cross was made between round, green seeds and wrinkled, yellow seeds. In the given cross, two traits were taken into account, thus it is a dihybrid cross.

Yellow colour and round shape is dominant over green colour and wrinkled shape.

Phenotype of all the plants is Round and yellow seeds.

The above cross shows round and yellow seeds in the F1 generation. It occurs because dominant traits (round and yellow) expresses itself in the heterozygous condition whereas recessive traits (wrinkled and green) get suppressed.

 (b) On selfing of F1 generation:

Phenotypic ratio − 9:3:3:1

Round yellow − 9

Round green − 3

Wrinkled yellow − 3

Wrinkled green −1