At the time of ovulation,secondary oocyte is arrested at Metaphase II and goes into the fallopian tube.If fertilization occurs, sperm binds with secondary oocyte and releases Anaphase promoting factor which leads to completion of meiosis II,ovum is formed and it subsequently gets converted into zygote. My question is that why formation of ovum is dependent on fertilization by sperm and why formation of sperms is independent process? Has it some benefits for nature?
This can only be answered logically. Imagine bellow paragraph. If secondary oocyte does not require fertilization for completing 2nd meiotic division then it will become an ootid (female gamete). Once formed lots of hormonal changes occur in female example individual's diet increase, mammary glands differentiate and all necessary changes for pregnancy which will be unnecessary at end of every month. I hope u understood and comment if u want to ask about above imaginary paragraph.
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