What is the frequency of plants with red flowers homozygotes

What is the frequency of plants with red flowers (homozygotes for CRCR) in a population if the frequency of the CW allele is 0.32 and the population is in H-W equilibrium? Assume that CW and CRare the only 2 alleles for flower color.

Solution

Answer:

Frequency of red flowers= C^RC^R

Frequency of C^W allele is 0.32

Let the frequency of the allele C^R = p,   and C^W = q

                           According to Hardy-Weinberg Equilibrium p+q =1

                                               so.    p+0.32= 1

                                                        p= 0.68

                                             now p= 0.68 and q= 0.32

      According to Hardy-Weinberg Equilibrium.                    

                                    p2 + 2pq + q2 = 1

                         p2 (C^RC^R) = 0.68 x 0.68 = 0.46

                        2pq(C^RC^W) = 2x 0.68 x 0.32 = 0.43

                        q2(C^WC^W) = 0.32 x 0.32 =0.10.

Frequency of plants with red flowers (homozygotes for C^RC^R) = 0.46 = 46%

The population is in H-W equilibrium, as it obeys p2 + 2pq + q2 = 1