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Principles of Inheritance and Variation
Briefly mention the contribution of T.H. Morgan in genetics.

Briefly mention the contribution of T.H. | 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 9: . 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 9: Briefly mention the contribution of T.H. Morgan in genetics.

Answer:

Morgan’s work is based on fruit flies (Drosophila melanogaster). He formulated the chromosomal theory of linkage. He defined linkage as the co-existence of two or more genes in the same chromosome and performed dihybrid crosses in Drosophila to show that linked genes are inherited together and are located on X-chromosome. His experiments have also proved that tightly linked genes show very low recombination while loosely linked genes show higher recombination.

Other Questions of Chapter Principles of Inheritance and Variation

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

Q: When a cross in made between tall plants with yellow seeds (Ttyy) and tall plant with green seed (Ttyy), what proportions of phenotype in the offspring could be expected to be (a) Tall and green. (b) Dwarf and green.

Q: Mention any two autosomal genetic disorders with their symptoms.

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: 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.

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: 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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Comments

Dhiraj
Oct 21, 2019

Thank you so much

Manasi
Sep 29, 2019

Nice answers Thanks a lot!!!

Rambabu
May 05, 2019

Thanks

Rambabu
May 05, 2019

Thanks

Aadi
Mar 03, 2019

Great work... Perfect and ans in very easy way ðð

SSD
Dec 09, 2018

Thank you so much Sarah study. You all are doing a great job.It's very helpful and supportive...

anu
Oct 20, 2018

useful to me

yash
Sep 09, 2018

fantestic answer

Devesh
Jun 16, 2018

Nice answer thnx a lot