Which follicle is selected to release the ovum and give rise to the corpus luteum?

• A. Dominant Graafian follicle
• B. Primary follicle
• C. Secondary follicle
• D. Antral follicle

Answer: (A)

The event of ovulation hinges on the mature, pre-ovulatory follicle—the dominant Graafian follicle—which is selected to release the ovum and later give rise to the corpus luteum. As the cycle progresses, this follicle becomes the most advanced in response to rising FSH and LH, and at the LH surge it ruptures to expel the oocyte. The remaining follicular cells undergo luteinization under LH influence to form the corpus luteum, which then secretes progesterone (with some estrogen) to support the luteal phase and early pregnancy. The other stages—primary, secondary, and antral follicles—are earlier developmental forms that do not ovulate or form the corpus luteum in the same way; they are parts of the growth process but not the follicle selected for ovulation.