Short answers, pulled from the story.
Karl Ernst von Baer discovered the mammalian ovum in 1827. This discovery shattered the long-held assumption that mammals reproduced differently from fish or birds and proved that the female contribution to reproduction was a distinct, visible cell.
Solomon Zuckerman concluded in 1950 that no new eggs were ever created after a female's birth. His comprehensive review of reports from 1900 to 1950 cemented the view that the production of immature egg cells ceased shortly after birth.
Maternal DNA recombines approximately 42 times on average in humans. This rate is higher than the paternal DNA recombination rate of approximately 27 times, suggesting the egg cell plays a more active role in shuffling genetic diversity.
The ooplasm functions as the cytoplasm of an ordinary animal cell containing spongioplasm and hyaloplasm to nourish the embryo during the earliest stages of development. It also contains the nucleus named the germinal vesicle and the nucleolus called the germinal disc.
Fifteen nurse cells die for every single oocyte that is produced in Drosophila. This programmed cell death or apoptosis ensures the egg has the necessary components to support early embryonic development.