formation

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Formation

A pattern on a chart indicating price movement in a security. See also: Technical analysis.

formation

References in periodicals archive ?
This seems a rough oversimplification of the meiotic process, because, as mentioned above, prophase pairing does not necessarily lead to chiasma formation.
formation of a chiasma involving one ann of a chromosome has no influence on the probability of chiasma formation involving the other arm; 2) pairing of one arm with another precludes involvement of a third; 3) the frequency (c) with which two chromosome arms pair is the same for all arms - i.
Darlington's first relevant contributions to the study of meiosis and chiasmata (before he turned almost exclusively to plants) were performed in gomphocerine grasshopper species (Chorthippus, Stauroderus), an extremely good material for cytogenetic work on male meiosis, because species of this group of genera (the 'truxaline' grasshoppers) not only have beautiful large-sized chromosomes, but also an asymmetric karyotype involving three metacentric homologous pairs of autosomes and five telocentric ones, allowing direct simultaneous comparisons of pairing and chiasma formation in both types of configurations (Darlington 1935, 1936, 1937; Darlington & Dark 1932).
In all cases, these abnormalities resulted from the apparent lack of chiasma formation between the metacentric (A chromosome) and one of the acrocentric elements.
Originally, White interpreted the problems of sex-chromosome evolution (mainly) by four approaches: the comparison of sizes and shapes of chromosomes at metaphase I, the study of the heteropycnosis of particular chromosomal regions, chiasma formation on homologous regions at meiosis and comparative studies in different groups (White 1940a,b, 1941a, b, 1960, 1973; Castillo et al.