NEET BIOLOGY

Detailed explanation-1: -An organism with one dominant allele and one recessive allele is said to have a heterozygous genotype. In our example, this genotype is written Bb. Finally, the genotype of an organism with two recessive alleles is called homozygous recessive. In the eye color example, this genotype is written bb.

Detailed explanation-2: -Genotypes with two alleles that are the same, i.e. ‘BB’ and ‘bb’, are known as homozygous genotypes and genotypes with two different alleles are known as heterozygous genotypes.

Detailed explanation-3: -Heterozygous means one dominant & one recessive allele. Since they are Type “B", the dominant allele is IB, & the only recessive allele for blood type is “i". So the both parents are IBi, & the cross is IBi x IBi.

Detailed explanation-4: -A heterozygous calf has one red allele and one black allele (Bb). These animals are always black. This tells you that the black allele is dominant and the red allele is recessive because the black coloration is hiding the red. We use “B” to indicate the dominant black allele and “b” for the recessive red allele.

Detailed explanation-5: -Predicting Offspring Phenotypes B is dominant to b, so offspring with either the BB or Bb genotype will have the purple-flower phenotype. Only offspring with the bb genotype will have the white-flower phenotype.