Maturing follicles. Light micrograph of a sectioned ovary showing follicles in different stages of maturation. Several primordial follicles (small purple circles, upper frame) mature during each menstrual cycle into secondary follicles (large purple and white bodies). Inside each secondary follicle is an enlarged oocyte (egg, smaller purple circles), surrounded by many granulosa cells (dark purple dots). A large fluid- filled space (the antrum, white) also develops. One secondary follicle per month becomes a Graafian follicle, releasing its oocyte at ovulation. Trichrome stained. Magnification: x11 at 35mm size.