polytene chromosome(redirected from Puff (chromosomal))
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a stage of chromosome division that forms the giant chromosome found in the salivary gland of dipterous insects; the great width is the result of repeated divisions of the chromonema without subsequent lengthwise separation of the filaments.
Synonym(s): giant chromosome (1)
Etymology: Gk, polys + tainia, band
an excessively large type of chromosome consisting of a large number of copies of the chromosome bundled side by side. Polytene chromosomes are produced by repeated rounds of DNA synthesis without mitosis and are bundles of unseparated chromonemata filaments found primarily in the salivary glands of certain insects. See also giant chromosome.