Primary follicle in feline ovary.

The primary follicle contains an oocyte surrounded by a single layer of cuboidal epithelial cells which sit on a basal lamina. This is a primary oocyte in arrested prophase of the first meiotic division. The nucleus is large and has a prominent nucleolus. Also seen in this micrograph are a number of primordial follicles. Each one of these contain an oocyte surrounded by a flattened layer of follicular cells. The oocytes are also primary oocytes. Compare the sizes between the primordial and primary follicles and you will see that the oocyte in the primary follicle has increased in size considerably. The stromal cells are small and spindle-shaped. A few chubby cells seen in the stroma are interstitial endocrine cells. PK1457. Original mag. 100x H&E Primary follicle and primordial follicles. Cortex. Ovary. Female Reproductive System. Cat.