AP BIOLOGY

Detailed explanation-1: -The primary oocyte is a diploid cell & is formed from the oogonia /gamete mother cell by mitotic division. It gives rise to secondary oocytes after the meiosis-I division. These secondary oocytes are haploid. These secondary oocytes undergo meiosis-II to form haploid ovum.

Detailed explanation-2: -Secondary oocyte, ova, secondary spermatocyte and spermatids are haploid in number, each with 23 chromosomes.

Detailed explanation-3: -The primary spermatocyte and primary oocyte undergo meiosis I, producing the 2n 2x secondary spermatocyte and secondary oocyte at the end of meiosis I.

Detailed explanation-4: -The secondary oocyte is the cell that is formed by meiosis I in oogenesis. Thus, it has only one of each pair of homologous chromosomes. In other words, it is haploid.