| polytene | A giant chromosome which is composed of thousands of copies of DNA parallel to one another instead of the usual one copy of DNA per chromosome. They are found in the salivary glands of insects, in certain protozoans, and in flowering plants. As found in the larvae of the fruit fly Drosophila melanogaster, they are useful to geneticists because all of the details are greatly enlarged. (09 Oct 1997) |
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| polytene chromosome | <cell biology> Giant chromosomes produced by the successive replication of homologous pairs of chromosomes, joined together (synapsed) without chromosome separation or nuclear division. They thus consist of many up to 1000) identical chromosomes (strictly chromatids) running parallel and in strict register. The chromosomes remain visible during interphase and are found in some ciliates, ovule cells in angiosperms and in larval Dipteran tissue. The best known polytene chromosomes are those of the salivary gland of the larvae of Drosophila melanogaster which appear as a series of dense bands interspersed by light interbands, in a pattern characteristic for each chromosome. The bands, of which there are about 5,000 in Drosophila melanogaster, contain most of the DNA (ca 95%) of the chromosomes and each band roughly represents one gene. The banding pattern of polytene chromosomes provides a visible map to compare with the linkage map determined by genetic studies. Some segments of polytene chromosome show chromosome puffs, areas of high transcription. (18 Nov 1997) |
| polytene |
composed of or containing many strands of chromatin (chromonemata).
출처: www.mercksource.com/pp/us/cns/cns_health_library.j...
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| polytene c.’s |
giant bundles of unseparated chromonemata occurring especially in the salivary glands of some insects; called also giant c's.
출처: www.mercksource.com/pp/us/cns/cns_health_library.j...
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제품명 |
판매사 |
보험코드 | 성분/함량 | 구분/보험급여 |
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제품명 |
판매사 |
보험코드 | 성분/함량 | 구분/보험급여 |
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