developmental gates maturation gate IDOMAL:0002279 IDOMAL:0002279 Oocytes that have reached stage V and are ready for ovulation are often described as mature, yet their chromosomes are still in the metaphase of the first meiotic division. Meiosis is resumed only after the oocytes have been penetrated by sperm at oviposition. Thus the oocytes are held in a state of nuclear stasis from the time they are ready for ovulation until syngamy stimulates completion of the maturation divisions. The maturation resting stage normally lasts only a few hours, until the appropriate activity rhythm leads to ovulation and oviposition. However, if females are unable to oviposit, the stage V oocytes can remain viable within ovaries for 15days or even more. idomal_namespace