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In salivary gland chromosomes/polytene c...

In salivary gland chromosomes/polytene chromosomes, pairing is

A

absent

B

occasional

C

formed between non-homologous chromosomes

D

formed between homologous chromosomes

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Verified by Experts

The correct Answer is:
D
Polytene chromosomes/salivary gland chromosomes was reported by Balbiani (1881) from cells of salivary glands of Chironomus larva (insect of Diptera droup). The polytene chromosomes become giant due to the endoduplication, i.e., repeated replication of chromatids without their separation and cytokinesis. In fact, each polytene chromosome is formed by pairing of two somatic homologous chromosomes which undergo repeated endomitosis to form numerous strands attached to a common large chromocentre.
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  7. Which of the folliwng structure will not be common to mitotic cell of ...

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  8. The exchange of genetic material between chromatids of paired homologo...

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  9. Lampbrush chromosomes are visible

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  10. The point at which the polytene chromosomes appeart to be attached tog...

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  11. Meiosis is evolutionary significant because it results in

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  12. Best stage to observe shape, size and number of chromosome is

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  13. In salivary gland chromosomes/polytene chromosomes, pairing is

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  14. Meiosis II performs

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  15. Balbiani rings (puffs ) are sites of

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  16. Number of chromatids per chromosome at metaphase is

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  17. In meiosis, the daughter cells differ from parent cell as well as amon...

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  18. Mitotic anaphase differs from metaphase in possessing

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  19. A bivalent of meiosis i consists of

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  20. Meiosis-I is reductional division. Meiosis-II is equational division d...

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