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The third stage of the prophase of meiosis, during which the homologous chromosomes become short and thick and divide into four distinct chromatids.

[French pachytène : Greek pakhus, thick + French -tène, ribbon (from Latin taenia; see taenia).]


(Biology) the third stage of the prophase of meiosis during which the chromosomes become shorter and thicker and divide into chromatids
[from Greek pakhus thick + tainia band]


(ˈpæk ɪ tin)

the third stage of prophase in meiosis, during which each chromosome pair separates into sister chromatids with some breakage and crossing over of genes.
[< French pachytène (1900) = Greek pachý(s) thick + French -tène -tene]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.pachytene - the third stage of the prophase of meiosis
prophase - the first stage of meiosis
phase, stage - any distinct time period in a sequence of events; "we are in a transitional stage in which many former ideas must be revised or rejected"
References in periodicals archive ?
Pachytene asynapsis drives meiotic sex chromosome inactivation and leads to substantial postmeiotic repression in spermatids.
Aneuploidies generated after a 24-hr test interval arise from the impairment of late meiotic (late pachytene and onward) and early embryonic processes, whereas the 65-hr interval captures aneuploidies originating from the disruption of any mitotic and meiotic events in the germline in addition to early embryonic stages.
Metabolism of pachytene primary spermatocytes from rat testes: Pyruvate maintenance of adenosine triphosphate level.
During pachytene stage in meiosis I, homologous pairing of Robertsonian translocation is achieved by the formation of a trivalent structure.
This latter cell gives rise to the primary spermatocyte, which quickly undergoes its first meiotic division and passes through 4 prophase stages, leptotene, zygotene, pachytene, and diplotene, before undergoing meiotic metaphase.
2-4), more intensive staining revealed overcondensation of the X chromosome from leptotene to pachytene (Fig.
Pachytene pairing and meiosis in the F1 hybrid of Pennisetum typhoides and P.
Population of preleptotene, pachytene, secondary spermatocytes and step-19 spermatid were declined by 60.
During a stage in spermatogenesis called the pachytene stage, genes in the X and Y chromosomes (known as the sex chromosomes because they determine the sex of the offspring) become inactive.
84%) deviation) (c) Testicular cell counts (number/10 cross section) Primary spermatocytes Preleptotene Pachytene Group-I 19.