At birth, the ovarian cortex has around two million follicles - that's roughly the population of Paris - and they're called primordial follicles.

出生时，皮质内的滤泡数量大概是200万，与整个巴黎的人口数相近，它们被叫做始基卵泡。

Meanwhile, the primordial follicle turns into a primary follicle, meaning that the follicular cells that surrounding the primary oocyte develop into granulosa cells.

与此同时，包围初级卵母细胞的滤泡细胞分化为颗粒细胞，使始基卵泡变为初级卵泡。

Each primordial follicle has a single immature sex cell called the primary oocyte at the core, and a layer of follicular cells surrounds this.

每一个始基卵泡中心都有一个未成熟的生殖细胞，叫做初级卵母细胞，被卵泡细胞包裹。