In poultry, black color is due to a dominant factor (B). The recessive color is red (b). A red male bird is mated to a black female. They produce many offspring, half of which are black and half red. What are the genotypes of the parents?
To determine the genotypes of the parents, we need to use the principles of Mendelian genetics.
Given:
- The black color in poultry is due to the dominant factor (B).
- The recessive color is red (b).
Note: In genetics, uppercase letters are typically used to represent dominant alleles, while lowercase letters represent recessive alleles.
Let's analyze the given information:
1. The offspring: Half of the offspring are black (B) and half are red (b). This suggests that the parents have different genotypes.
2. The male bird is red. So, the male bird should have two recessive alleles (bb) since red color is recessive.
3. The female bird is black. This means that the female can have either one or two dominant alleles (BB or Bb) since black color is due to the dominant factor.
Based on this information, we can determine the genotypes of the parents as follows:
- Male bird (red): bb (both alleles are recessive)
- Female bird (black): Since half of the offspring are black and the other half are red, this suggests that the female bird has one dominant allele (B) and one recessive allele (b). Therefore, the genotype of the female bird is Bb.
In summary:
- Male bird (red): bb
- Female bird (black): Bb