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प्रश्न
Who had proposed the chromosomal theory of inheritance?
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उत्तर
Sutton and Boveri independently proposed the chromosomal theory of inheritance in 1902. The two workers found a distinctive connection between the transmission of Mendelian hereditary elements (genes) and chromosome activity during gamete production and fertilisation. They proposed that chromosomes carried Mendelian factors. During meiosis, both chromosomes and genes segregate and assort independently before recombining in the zygote during fertilisation. Morgan, Sturtevant, and Bridges enlarged upon the chromosomal theory of inheritance.
संबंधित प्रश्न
If the number of chromosomes in an endosperm cell is 27, what will be the chromosome number in the definitive nucleus?
- 9
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- 27
- 36
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A B B C C D E F G H I
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P - Due to presence of large amount of euchrornatin X chromosome is genetically more active.
Q - Due to presence of small amount of heterochromatin Y chromosome is genetically more active.
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From the following identify the INCORRECT statement/s with respect to the chromosomes.
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iv. The number of chromosomes varies within the population of a particular species.
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i. Non-homologous region of X chromosome is longer and contains more genes than that of non-homologous region of Y chromosome.
ii. X-linked genes are present on nonhomologous region of X-chromosome.
iii. Y-linked genes are present on homologous region of Y-chromosome.
iv. Crossing over occurs only between homologous regions of X and Y chromosomes.
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Which three scientists independently rediscovered Mendel’s work?
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