Question

In sweet pea plants, the presence of dominant C and P genes is essential for development of purple colour. The ratio of plants producing flowers of different colours in the progeny of the cross ccPP × Ccpp will be

Answer 1

Hello there!

In this question, there are only two types of coloration/pigmentation in your flowers—purple (C_P_) or white (c_p_).

Remember that as long as the flower has a one dominant C and one dominant P then the coloration of the flower is purple. Otherwise, coloration is white.

1. Let's take the cross ccPP X Ccpp

• The cross of gene C will result to:

               1/2 Cc and 1/2 cc

• The cross of gene P will result to:

               all (1) Pp

    2.  Let's follow product law to find the possible genotypes in this cross.

      1/2 Cc * 1 Pp= 1/2 CcPp --> phenotype is purple flower

      1/2 cc * 1 Pp= 1/2 ccPp --> phenotype is white flower

Therefore, the ratio is 1 purple flower: 1 white flower.

I hope this will help you!