The development of the secondary follicle involves a series of complex hormonal and cellular events. The primary follicle, which contains a single layer of granulosa cells, begins to acquire more layers, and the surrounding stromal cells differentiate into theca cells. These theca cells form two distinct layers: the theca interna and the theca externa. The theca interna cells are responsible for producing androgens, which are later converted to estrogens by the granulosa cells.
