1. |
Effect of the Mutagens Hydroxylamine, Ethyl Methane Sulphonate and Gamma Rays Separately and in Combination on Meiotic Chromosomes |
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Caryologia,
Volume 24,
Issue 1,
1971,
Page 1-11
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摘要:
The effects of the mutagens hydroxylamine, ethyl methane sulphonate and gamma rays separately and in combination were studied on the meiotic chromosomes in the M1generation of an inbred strain ofPennisetum typkoides.The significant findings were as follows:
ISSN:0008-7114
DOI:10.1080/00087114.1971.10796406
出版商:Taylor & Francis
年代:1971
数据来源: Taylor
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2. |
Cytogenetic Study of Triploid Maize and the Frequency of Aneuploids |
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Caryologia,
Volume 24,
Issue 1,
1971,
Page 13-18
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摘要:
The study of meiosis performed on 53 triploidZea maysplants revealed the occurrence of 1.48 I per cell in metaphase I, an unbalanced disjunction of chromosomes in anaphase I (the 15-15 type being only 32.66% in frequency) and a relatively high frequency of laggards and micronuclei. Consequently, the pollen fertility is low (44.58%) and the offspring 3nplants shows forms with 17-42 chromosomes, with a clear predominance of hyper triploids (81.0%).
ISSN:0008-7114
DOI:10.1080/00087114.1971.10796407
出版商:Taylor & Francis
年代:1971
数据来源: Taylor
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3. |
Cytogenetical Evaluation of the Progenies of a Trispecific Hybrid inPennisetum |
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Caryologia,
Volume 24,
Issue 1,
1971,
Page 19-26
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摘要:
The trispecific hybridP. squamulatumx amphidiploid(P. typhoidesxP. purpureum)bad 2n=48 chromosomes. The pairing of chromosomes in meiosis revealed the existence of homology of chromosomes of the parental species.
ISSN:0008-7114
DOI:10.1080/00087114.1971.10796408
出版商:Taylor & Francis
年代:1971
数据来源: Taylor
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4. |
Cytogenetical Studies inErianthusII: Ocurrence of Chromosome Knobs |
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Caryologia,
Volume 24,
Issue 1,
1971,
Page 27-31
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摘要:
Occurrence of terminal knobs on the chromosomes ofEriantbus elephantinusandErianthus ravennaepossessing twenty somatic chromosomes was observed. This is the first report of chromosome knobs in the genusErianthus.
ISSN:0008-7114
DOI:10.1080/00087114.1971.10796409
出版商:Taylor & Francis
年代:1971
数据来源: Taylor
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5. |
The Course of Mitosis in Young Embryos ofAscidiella Aspersa(Ascidiacea) |
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Caryologia,
Volume 24,
Issue 1,
1971,
Page 33-39
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摘要:
According to the morphology and behaviour of chromosomes and to the kinetic of the mitotic events, the embryonic mitosis ofAscidiella aspersahas been divided into 6 well distinguishable phases: prophase, prometaphase, metaphase, anaphase, anatelophase and telophase.
ISSN:0008-7114
DOI:10.1080/00087114.1971.10796410
出版商:Taylor & Francis
年代:1971
数据来源: Taylor
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6. |
The Protective Influence of Cysteine and Glutathione Against Radiation Induced Chromosome Damage inHordeum VulgareRoot Tips |
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Caryologia,
Volume 24,
Issue 1,
1971,
Page 41-47
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摘要:
Experiments were performed to study the protective property of 5 × 10−2M cysteine and 2 × 10−3M glutathione against radiation induced chromosome damage in the root tips ofHordeum vulgare.The protective ability was examined by scorings in anaphase cells 24 hours after 200, 400 and 600r of X-irradiation. It was found that cysteine showed a more significant level of protection against radiation induced chromosome fragments, fragments and bridges or bridges than did glutathione.
ISSN:0008-7114
DOI:10.1080/00087114.1971.10796411
出版商:Taylor & Francis
年代:1971
数据来源: Taylor
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7. |
The Ultrastructure of the Kinetochores ofLilium LongiflorumDuring the first Meiotic Division |
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Caryologia,
Volume 24,
Issue 1,
1971,
Page 49-58
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摘要:
The kinetochores of the first meiotic divisions ofLilium longiflorumappear less electron-dense than the majority of the chromatin, are roughly spherical, and consist of fine fibrils 10–20 nm in diameter. The fine structure observed here appears to be consistent with several previous studies by other workers on higher plants. However, many variations in the observed fine structure of kinetochores of both plants and animals appear in the literature. Possible sources of the discrepancies in the observations are variations in interpretation of electron micrographs, variations in fixation procedures, and variations due to genuine phylogenetic differences of the organisms studied.
ISSN:0008-7114
DOI:10.1080/00087114.1971.10796412
出版商:Taylor & Francis
年代:1971
数据来源: Taylor
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8. |
The Karyology ofClavelina LepadiformisMueller (Ascidiacea) |
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Caryologia,
Volume 24,
Issue 1,
1971,
Page 59-64
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摘要:
The embryonic mitosis ofClavelina lepadiformisis characterized by the presence of precociously separating daughter kinetochores and by an extreme shortening of chromosomes during prophase and prometaphase. The chromosomes ofClavelina lepadiformisare all metacentric; differentiated sex chromosomes are not present. The same haploid number of chromosomes,n=9, has been found in both populations of the Lagoon of Venice and of the west coasts of Scotland. Both oocyte and spermatocyte bivalents possess chiasmata.
ISSN:0008-7114
DOI:10.1080/00087114.1971.10796413
出版商:Taylor & Francis
年代:1971
数据来源: Taylor
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9. |
The Chromosomes ofPhallusia MammillataCuvier (Ascidiacea) |
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Caryologia,
Volume 24,
Issue 1,
1971,
Page 65-70
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摘要:
The course of embryonic mitosis ofPhallusia mammillatacan be characterized by it short duration, the occurrence of precociously separating daughter kinetochores, the somatic association of homologous chromosomes and by the precociously uncoiling of chromosomes at late anaphase.
ISSN:0008-7114
DOI:10.1080/00087114.1971.10796414
出版商:Taylor & Francis
年代:1971
数据来源: Taylor
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10. |
Behaviour of Dicentric Chromosomes in Peas |
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Caryologia,
Volume 24,
Issue 1,
1971,
Page 71-84
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摘要:
The variegated mutant P 17 characterized by the presence of dicentric chromosomes was induced by X-irradiation of pollen with 750 R. This dicentric chromosomes is persistant and transmissible; both centromeres are active and the intercentromeric region is long enough to allow the formation of criss-cross and parallel double bridges. Mitotic behaviour of the dicentric chromosome determines a mixochimeric structure wich causes a mosaic phenotype pattern. Associations of the dicentric with more than two chromosomes at metaphase I shows that the dicentric chromosome is heterodicentric.
ISSN:0008-7114
DOI:10.1080/00087114.1971.10796415
出版商:Taylor & Francis
年代:1971
数据来源: Taylor
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