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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 ?
These cells are found associated with the spermatogonia type B, pachytene spermatocytes and Sertoli cells.
Based on the microscopic diagnosis of the germ lineage, cysts with a batch of oogonia surrounded by prefollicle cells, pachytene oocytes, primary growth oocytes, early and late secondary growth oocytes, a full-grown oocyte (Figure 2 and Table 1) and oocyte maturation (Figure 3J) were recognized in S.
In rat testicular cells, G protein [alpha]-subunits and their mRNA were expressed in pachytene spermatocytes, round spermatids, Sertoli cells, and peritubular cells (Paulssen et al.
Primary spermatocytes, stained with the anti-SCP3 antibody, were selected to evaluate the respective percentages of leptotene, zygotene, pachytene and diplotene stages.
The preleptotene spermatocytes enter prophase I of meiosis, transform into leptotene, zygotene, pachytene and diplotene cells, which then quickly finish meiosis I forming secondary spermatocytes.
In these spermatocytes, the chromatin in the nucleus of the pachytene oocytes, even more condensed, takes the shape of an umbrella (Fig.
In the case of non-irradiated larvae, relative sizes of chromosome pairs in pachytene cells were measured using the computer application MicroMeasure version 3.
Synaptic behaviour and morphological modifications of the X and Y chromosomes during pachytene in three species of Ctenomys (Rodentia, Caviomorpha, Ctenomyidae).
Different levels of a lack of X-Y chromosome pairing in pachytene spermatocytes of red fox (Vulpesvulpes) and Chinese raccoon dog (Nyctereutesprocyonoidesprocyonoides).
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.