CHANGE IN THE ROENTGEN-RADIATION SENSITIVITY OF THE MICROSPORES OF TRADESCANTIA PALUDOSA IN THE COURSE OF MITOSIS (in Russian)
To calculate the number of chromosome rearrangements occurring in x irradiation during mitosis, microspores of Tradescantia paludosa, in which spontaneous rearrargements do not occur, were irradiated with 200 r. The sensitivity to radiation of the first postmeiotic phase was observed, and the rearrangements in the metaphases of the two subsequent mitoses were calculated. The relative sensitivity of the phases was established as: early interphase/ late interphase/early prophase/late prophase/anaphase equals 1.0/1.1/1.8/5.5/6.1. The ratio of dicentrics to circulars in both early and late interphase was three, in early and late prophase was five, and in anaphase was eight. Therefore exchange between the arms in one chromosome takes place more often in interphase than in the other phases, probably because of the long arms in this phase. In irradiation of the different phases the chromosome breaks as a single thread and in irradiation of the prophase the chromosome breaks as a double thread. Irradiation of the late prophase results in a polychromatid rearrangement in 1.2 percent of the cases which is of a type indicating a quaternary rupture. (TTT)
- Research Organization:
- Inst. of Biophysics, Moscow
- NSA Number:
- NSA-17-031937
- OSTI ID:
- 4674004
- Journal Information:
- Radiobiologiya (U.S.S.R.) For English translation see Radiobiology (Engl. Transl.), Journal Name: Radiobiologiya (U.S.S.R.) For English translation see Radiobiology (Engl. Transl.) Vol. Vol: 3; ISSN RADOA
- Country of Publication:
- Country unknown/Code not available
- Language:
- Russian
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