The number of pairs of loops gradually increases in meiosis till it reaches maximum in diplotene. As meiosis proceeds further, number of loops gradually decreases and the loops ultimately disappear due to disintegration rather than reabsorption back into the chromomere. H. Ris, however, had thought that the loops were integral parts of chromonemata which are extended in the form of major coils. It is also believed that the loops represent the modified chromosome structures at the loci of active genes. It has been observed that, if the activity of these genes is stopped by actinomycin D (actinomycin D stops synthesis of RNA on DNA template), the loops will collapse, suggesting that the loops mainly consist of RNA.
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