This is image shows a high magnification view of a slice through an ovary.
You are looking at four tiny primordial follicles (the cookies above Cookie Monster’s head) located in the outer cortex of the ovary. Each of these follicles contains a single dormant, immature egg (a primary oocyte) that is halted in the the first phase of meiosis (prophase I). Eventually these follicles will be recruited to enter the maturation cycle that, against all the odds, could see them develop into an embryo.
Cookie monster himself is a larger multilaminar primary follicle (the cookie in his mouth is the nucleus of the oocyte within the follicle). This type of follicle has already been recruited and it’s follicular cells are dividing and differentiating. The oocyte within it though is still halted in prophase I of meiosis.
An oocyte will only complete meiosis if it is ovulated and fertilized by a spermatozoon (a sperm cell).
