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.
Well, the body has a endless supply of energy (even if you have an energy drink or a lot of coffee) but anyway we will always have a lot of energy until you have to go to the other world (if you know what I mean)
I'm pretty sure it's Cell membrane