From the Research
The probable phenotypic ratio in the offspring of a pair of blue chickens is 25% white, 50% blue, 25% black (option C). This pattern indicates incomplete dominance, where neither the white nor black allele is completely dominant over the other. When a white rooster (let's say genotype WW) is crossed with a black hen (genotype BB), all offspring are heterozygous (WB) and show an intermediate blue phenotype. When these blue chickens mate with each other, the offspring follow a 1:2:1 ratio according to Mendelian genetics. The possible genotypic combinations are WW (white), WB (blue), and BB (black), with the heterozygous blue phenotype appearing twice as frequently as either homozygous phenotype. This is a classic example of incomplete dominance where the heterozygous condition produces an intermediate phenotype rather than one trait being fully dominant over the other. None of the provided studies 1, 2, 3, 4, 5 are relevant to the question of phenotypic ratios in chicken offspring, as they pertain to human health and medicine. However, based on general knowledge of genetics, the answer can be determined. Key points to consider include:
- Incomplete dominance, where the effect of one allele is not completely masked by the other
- Mendelian genetics, which predicts the probability of different genotypes and phenotypes in offspring
- The specific genotypic combinations and their corresponding phenotypes in this scenario.