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A child has blood group O. If the father has blood group A and mother ...

A child has blood group O. If the father | Class 12 Biology Chapter Principles of Inheritance and Variation, Principles of Inheritance and Variation NCERT Solutions

Welcome to the NCERT Solutions for Class 12 Biology - Chapter Principles of Inheritance and Variation. This page offers a step-by-step solution to the specific question from Exercise 1, Question 12: . With detailed answers and explanations for each chapter, students can strengthen their understanding and prepare confidently for exams. Ideal for CBSE and other board students, this resource will simplify your study experience.

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.

Answer:

The blood group characteristic in humans is controlled by three set of alleles, namely, I^A, I^B, and i. The alleles, I^A and I^B, are equally dominant whereas allele, i, is recessive to the other alleles. The individuals with genotype, I^A I^A and I^A i, have blood group A whereas the individuals with genotype, I^B I^B and I^B i, have blood group B. The persons with genotype I^A I^Bhave 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

I^A I^A or I^A i I^B I^B or I^B i

A cross between homozygous parents will produce progeny with AB blood group.

progeny with AB blood group

A cross between heterozygous parents will produce progenies with AB blood group (I^AI^B) and O blood group (ii).

progenies with AB & O blood group

Other Questions of Chapter Principles of Inheritance and Variation

Q: Explain the Law of Dominance using a monohybrid cross.

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Q: Who had proposed the chromosomal theory of inheritance?

Q: Two heterozygous parents are crossed. If the two loci are linked what would be the distribution of phenotypic features in F1 generation for a dihybrid cross?

Q: What is pedigree analysis? Suggest how such an analysis, can be useful.

Q: A diploid organism is heterozygous for 4 loci, how many types of gametes can be produced?

Q: Briefly mention the contribution of T.H. Morgan in genetics.

Q: Using a Punnett square, work out the distribution of phenotypic features in the first filial generation after a cross between a homozygous female and a heterozygous male for a single locus.

Q: Define and design a test − cross?

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Study Tips for Answering NCERT Questions:

NCERT questions are designed to test your understanding of the concepts and theories discussed in the chapter. Here are some tips to help you answer NCERT questions effectively:

Read the question carefully and focus on the core concept being asked.
Reference examples and data from the chapter when answering questions about Principles of Inheritance and Variation.
Review previous year question papers to get an idea of how such questions may be framed in exams.
Practice answering questions within the time limit to improve your speed and accuracy.
Discuss your answers with your teachers or peers to get feedback and improve your understanding.

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Comments

Srishti
Jun 13, 2019

Thank you

alanor george steward
Mar 27, 2019

thank u.......

alanor george steward
Mar 27, 2019

thanks .... seriously this is the very important question .....perhaps this question is being continuously asked for about 5 yrs........

Deepak
Mar 08, 2019

ðthank u