Mature and immature follicles. A size comparison.
In this low power picture of the ovary (8x) you can see the relative sizes of two mature secondary follicles and that of an early secondary follicle with a small antrum. In large follicles the oocyte may not be present in the section due to the plane of section. Very large mature follicles, as those seen shortly before ovulation, are also known as Graafian follicles. PK4892-24. Original mag. 8x. H&E. Secondary follicles. Cortex. Ovary. Female Reproductive System. Cat.