AP BIOLOGY

Detailed explanation-1: -In oogenesis, diploid oogonium go through mitosis until one develops into a primary oocyte, which will begin the first meiotic division, but then arrest; it will finish this division as it develops in the follicle, giving rise to a haploid secondary oocyte and a smaller polar body.

Detailed explanation-2: -Oogonia proliferate via mitosis during the 9th to 22nd week of embryonic development. There can be up to 600, 000 oogonia by the 8th week of development and up to 7, 000, 000 by the 5th month. Eventually, the oogonia will either degenerate or further differentiate into primary oocytes through asymmetric division.

Detailed explanation-3: -As a result, oogenesis is normally a one-mitosis, half-meiosis process, but when oogenesis is followed by fertilization, it is a one-mitosis, one-meiosis process.

Detailed explanation-4: -Oogonia are tiny diploid germ cells that pass through mitotic divisions and originate the primary oocytes.