Results 321 to 330 of about 199,391 (364)

THE PAIRING OF AN ALIEN CHROMOSOME WITH HOMOEOLOGOUS CHROMOSOMES OF WHEAT

Canadian Journal of Genetics and Cytology, 1972
The homoeology of chromosome A of Triticum umbellulatum has been determined by studying its pairing relationships with wheat telocentrics in hybrids having the chromosome constitution of 20 wheat chromosomes + one wheat telocentric chromosome + seven Triticum speltoides chromosomes + chromosome A.
Gordon Kimber, Raghbir S. Athwal
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THE EFFECT OF COLCHICINE ON CHROMOSOME PAIRING

Canadian Journal of Genetics and Cytology, 1977
Beginning at 120 hours prior to first metaphase of meiosis (MI) a 0.03% aqueous solution of colchicine was injected into the boot of pentaploid (hexaploid triticale × tetraploid wheat) hybrids developing at 20 °C ± 1° under continuous illumination. Colchicine applied 40 h or less prior to MI had no effect on chromosome pairing, while its application 40 
P. J. Kaltsikes, J. B. Thomas
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Joint Classification and Pairing of Human Chromosomes

IEEE/ACM Transactions on Computational Biology and Bioinformatics, 2005
We reexamine the problems of computer-aided classification and pairing of human chromosomes, and propose to jointly optimize the solutions of these two related problems. The combined problem is formulated into one of optimal three-dimensional assignment with an objective function of maximum likelihood. This formulation poses two technical challenges: 1)
Abhijit Sinha, Xiaolin Wu, Pravesh Biyani   +2 more
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Mechanism of Chromosome Pairing during Meiosis

Nature, 1970
Electron microscopy with whole mount preparations has revealed that the synaptonemal complex merely pulls two homologous chromosomes together. Intimate molecular pairing is another matter—probably brought about by connexions between short stretches of single stranded DNA.
David E. Comings, Tadashi A. Okada
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A cytophotometric study of chromosome pairing

Chromosoma, 1956
1. Confirming earlier studies (Schrader 1945a and b), the chromosomes of the harlequin lobe of the testis of the pentatomid Loxa flavicolis are found to be asynaptic throughout late meiotic prophase and to divide equationally at metaphase I. All other lobes show a normal meiosis. 2.
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Chromosome Pairing in Autotetraploid Lolium

Biochemie und Physiologie der Pflanzen, 1973
Summary Cytological investigations have been made in the autotetraploids of two species ( Lolium temulentum and L. persicum ). Correlations between different meiotic metrics were computed. Comparisons between the tetraploids and their diploid parents were also made.
C. P. Malik, R.C. Tripathi, T.N. Mary
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CHROMOSOME PAIRING IN HEXAPLOID TRITICALE [PDF]

Canadian Journal of Genetics and Cytology, 1971
A durum wheat background was shown to suppress the meiotic pairing of chromosomes of Secale montanum Guss. with homoeologues of S. cereale L. in hexaploid triticale. This effect was attributed to the activity of the 5BL diploidising system, apparently active in tetraploid wheat.
J. B. Thomas, P. J. Kaltsikes
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Chromosome pairing in haploids of Brassica campestris

Theoretical and Applied Genetics, 1981
The maximum chromosome pairing observed in haploids of Brassica campestris was two bivalents plus one trivalent but differences were observed in the chromosome pairing frequencies of the four haploids studied. This pairing supports the theorem that the species is hexasomic for one chromosome, tetrasomic for two and disomic for three others but it is ...
K. C. Armstrong, W. A. Keller
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CHROMOSOME PAIRING AND PHYLOGENETIC AFFINITIES

TAXON, 1972
SummaryThe mechanisms of chromosome pairing are poorly understood. Yet, pairing during meiotic prophase is commonly assumed to indicate homology, and absence of pairing non‐homology between parental genomes. These assumptions lead to the widely accepted belief that data on chromosome pairing in hybrids provide indisputable evidence of degree of ...
J. M. J. Wet, J. R. Harlan
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The Analysis of Chromosome Pairing

1975
In respect to chromosome pairing, two situations may be distinguished: non-competitive pairing, in which only two possible partners are available, and competitive pairing, where more than two potential partners are available, but where nevertheless only two at a time can finally pair sufficiently effectively to form a chiasma.
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