Occurrence: Spermatogenesis occurs inside the seminiferous tubules of a testis whereas oogenesis occurs inside the ovary. The product form in spermatogenesis is sperm which is flagellated i.e. motile and the product form in an Oogonium is ovum which is non-motile.
I think this is an theory changing because a new scientific method was developed. They used what Mendel had learned to test the hypothesis themselves and discovered that he was right.
Ants
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