NCERT Solutions for Class 12 Biology Chapter 5 Principle of Inheritance and Variation
Important Board Questions
Principle of Inheritance and Variation
NCERT Books for Session 2022-2023
CBSE Board and UP Board
Question : 12
A child has blood group O. If the father has blood group A and mother blood group B, work out the genotypes of the parents and the possible genotypes of the other offsprings.
Share
The blood group characteristic in humans is controlled by three set of alleles, namely, Iá´®, Iá´¬, and i. The alleles, IA and IB, are equally dominant whereas allele, i, is recessive to the other alleles. The individuals with genotype, Iá´¬ Iá´¬ and Iá´¬ i, have blood group A whereas the individuals with genotype, Iá´® Iá´® and Iá´® i, have blood group B. The persons with genotype IA IB have blood group AB while those with blood group O have genotype ii.
Hence, if the father has blood group A and mother has blood group B, then the possible genotype of the parents will be
Father Mother
Iá´¬ Iá´¬ or Iá´¬ i Iá´® Iá´® or Iá´® i
A cross between homozygous parents will produce progeny with AB blood group.
A cross between heterozygous parents will produce progenies with AB blood group (Iá´¬Iá´®) and O blood group (ii).
For more answers visit to website:
https://www.tiwariacademy.com/ncert-solutions/class-12/biology/chapter-5/