Punnett squares are used to show possible combinations of alleles or to predict the probability of a trait occurring in offspring. A parakeet that is heterozygous for blue feathers (dominant) is crossed with a parakeet that is homozygous for white feathers (recessive)
I'm not sure what you want answered but the ratio of the offspring would be 2:2. 50 percent chance of blue and 50 percent chance of white. The genotypes would be Bb,Bb,bb,bb
