Oogenesis is the formation of eggs/ova in the ovary.
Primordial germ cell-----Mitotic divisions--->
Oogonia (2n)-----Mitotic divisions--->
Primary oocyte (2n) - present at birth arrested at prophase I, at puberty completion of meiosis I and onset of meiosis II--->
Secondary oocyte (n) + 1st polar body - arrested at metaphase II----Ovulation/Sperm entry--> Completion of meiosis II-->
Fertilised egg + 2nd polar body
In fertilised egg there is an unequal clevage of cytoplasm to provide nutrients for the developing embryo.
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