Differentiate between spermatogenesis and oogenesis. how do these differences relate to the role of makes and female reproduction

Spermatogenesis takes place in the testes of males, oogenesis takes place in the ovary of the females.
Spermatogenesis produces small, motile spermatozoa whereas in oogenesis the ovum is spherical, not motile and is much larger with more food reserves and cytoplasm.
Spermatogenesis involves a metamorphosis stage called spermiogenesis, in oogenesis there is no metamorphosis stage.
In spermatogenesis, 4 gametes are produced from each meiotic division, whereas in oogenesis there is only 1 gamete produced from each division as the unequal cytokinesis leads to the formation of polar bodies.
Spermatogenesis occurs in males (human males) continuously from puberty to death whereas oogenesis starts in females at puberty and then occurs on a monthly basis until the menopause. It takes 70 days for sperm to be produced in males. 
In oogenesis, the development of the oocyte is arrested at prophase I of meiosis until puberty, and then stops at metaphase II of meiosis until fertilisation, where the meiotic division is finally completed. In males meiosis occurs continuously
The hormones in the 2 processes have different effects - in oogenesis, FSH is responsible for the choice of the primary oocyte and causes the cells of the membrana granulosa to proliferate to form the theca interna which secretes oestrogen, and the theca externa. LH in females stimulates ovulation and the maturation of the Graafian follicle. In males, on the other hand, FSH increases the activity of the Sertoli cells which are involved in spermiogenesis (the metamorphosis stage of spermatogenesis). LH in males stimulates the Leydig cells to secrete testosterone

Early atmosphere of earth had less oxygen (had more carbon dioxide and ammonia) hence was a non-reducing atmosphere. Most bacteria that thrived were anaerobes. However, the emergence of cyanobacteria approximately 3.5 million years ago filled the atmosphere with oxygen. This is because cyanobacteria respire out oxygen. The atmosphere thenceforth became reducing and hence most anaerobes perished while aerobics thrived. This is referred to as the Great Oxidization Event. The formation of ozone layer also enabled thriving of life since the UV light from sunlight was blocked and hecne could not damage organic molecules.