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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).]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(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]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(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]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
Arrest of spermatocytes at this stage indicated a failure of the cells to accomplish successful transition from zygotene to pachytene. At the ultrastructural level the mitochondria of the spermatocytes showed early evidence of disruption.
Male germ cells used in this study derived from two time points during development: pachytene spermatocyte (PS) acquired during prophase of meiosis I, and round spermatid (RS) acquired after completing meiosis.
demonstrated that the CDC25A protein was found in the cytoplasm of spermatogonial cells, pachytene spermatocytes stages, early to elongated spermatids from testicular tissue samples (31).
Type A spermatogonia at the basal lamina of seminiferous tubules, as well as primary spermatocytes in the leptotene and pachytene stages of prophase I, were also observed in the seminiferous epithelium.
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.
It is reported that Ku proteins are downregulated in early meiotic cells, but are again expressed in late pachytene and diplotene spermatocytes, and they mediate repair proficiency in somatic cells of the testis, thereby assuring the fidelity of spermatogenesis [11-13].
The sister chromatids form linear arrays of chromatin loops which are connected at their bases by the axial element, which is the precursor of the lateral element of the synaptonemal complex at pachytene [145].
Won Yoon et al., "GLI1 localization in the germinal epithelial cells alternates between cytoplasm and nucleus: upregulation in transgenic mice blocks spermatogenesis in pachytene," Biology of Reproduction, vol.
[42] found that a high temperature induced a rapid increase in reactive oxygen in pachytene spermatocytes but not in round spermatids.
[21] observed high levels of miRNA-34c in adult pachytene spermatocytes and round spermatids being important to the first cell division via modulating BCL2 expression, which is a direct target of miRNA-34c.