<prompt> In oogenesis, which of the following events occurs immediately following the completions of meiosis II?Degeneration of the zona pellucidaSperm penetration of the corona radiataFormation of a female pronucleusAppearance of the blastocyst  <response>: The secondary oocyte is arrested in metaphase of meiosis II, and it will remain in this meiotic stage until feilization occurs. Following feilization, the secondary oocyte completes meiosis II, forming a mature ovum and a polar body. The nucleus of the mature ovum is called the female pronucleus, which fuses with the male pronucleus to form a zygote. 