Editing Prophase (section)

==Prophase I arrest==
Female mammals and birds are born possessing all the oocytes needed for future ovulations, and these [[oocyte]]s are arrested at the prophase I stage of [[meiosis]].<ref name = Mira1998>{{cite journal | vauthors = Mira A | title = Why is meiosis arrested? | journal = Journal of Theoretical Biology | volume = 194 | issue = 2 | pages = 275–87 | date = September 1998 | pmid = 9778439 | doi = 10.1006/jtbi.1998.0761 | bibcode = 1998JThBi.194..275M }}</ref>  In humans, as an example, oocytes are formed between three and four months of [[gestation]] within the fetus and are therefore present at birth.  During this prophase I arrested stage ([[dictyate]]), which may last for decades, four copies of the [[genome]] are present in the oocytes.  The adaptive significance of prophase I arrest is still not fully understood.  However, it has been proposed that the arrest of oocytes at the four genome copy stage may provide the informational redundancy needed to [[DNA repair|repair damage in the DNA]] of the [[germline]].<ref name = Mira1998/>  The repair process used appears to be [[homologous recombination]]al repair<ref name = Mira1998/><ref name = Stringer2020>{{cite journal | vauthors = Stringer JM, Winship A, Zerafa N, Wakefield M, Hutt K | title = Oocytes can efficiently repair DNA double-strand breaks to restore genetic integrity and protect offspring health | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 117 | issue = 21 | pages = 11513–11522 | date = May 2020 | pmid = 32381741 | pmc = 7260990 | doi = 10.1073/pnas.2001124117 | bibcode = 2020PNAS..11711513S | doi-access = free }}</ref> Prophase arrested oocytes have a high capability for efficient repair of [[DNA damage (naturally occurring)|DNA damages]].<ref name = Stringer2020/>  DNA repair capability appears to be a key quality control mechanism in the female germ line and a critical determinant of [[fertility]].<ref name = Stringer2020/>