What cells during the follicular phase of the ovarian cycle secrete a thick gel-like material called the Zona Pellucida?

I believe it is formed by secretions from the oocyte and the follicle granulosa cells. The human oocytes consists of four types of zona pellucida glycoproteins ZP1, ZP2, ZP3, and ZP4 which have different roles in fertilization.

stress fractures occur largely in the feet and legs and are common in sports that require repetitive impact, primarily running/jumping sports such as gymnastics or track and field.