Answer to Question #166383 in Genetics for Ravi

Question

Pp×PP parents.predict the genotype and phenotype of F1,F2 after the test cross with diagram of test cross?

Answer 1

The gene for the purple flower color is dominant over the white flower color gene. Thus in both homozygous PP and heterozygous Pp conditions, the color of the flower will be purple. In this case, the test cross is done to identify whether the parent is homozygous or heterozygous. In the test cross, the parent (for which we want to find out the genotype) is crossed with the other homozygous recessive parent. In the above case, homozygous parent PP (purple flower) is crossed with the homozygous recessive parent pp (white flower).

Parents                  PP X pp (Test cross)

Gametes                 P     p

F1 generation          Pp (purple flower)

F2 generation

 

The phenotype of F2 generation: purple flower