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Principles of Inheritance and Variation — BIOLOGY STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceBIOLOGYPrinciples of Inheritance and Variation4 Marks
Question
Briefly mention the contribution of T.H. Morgan in genetics.
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Answer

TH Morgan's contribution in genetics are:
  • Morgan contributed to the understanding of sex-linked traits.
  • He carried out several experiments on fruit flies and his dihybrid crosses revealed that genes for some traits did not segregate independently and the F2 ratio was a lot different from 9 : 3 : 3 : 1.
  • He inferred that when two genes were situated on the same chromosome, the proportions of parental gene combinations were significantly higher than the non-parental type.
  • He established the principle of linkage crossing over, sex-linked inheritance and discovered the relation.
  • He established the technique of chromosome mapping.
  • He observed and worked on mutation.

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