What is the name of the structure in the ovary that produces progesterone?

The structure in the ovary responsible for producing progesterone is known as the corpus luteum. After ovulation, when an egg is released from a follicle, the remnants of the Graafian follicle transform into the corpus luteum. This temporary endocrine structure plays a crucial role in regulating the menstrual cycle and maintaining the early stages of pregnancy by secreting progesterone, which prepares the uterine lining for potential implantation of a fertilized egg.

Graafian follicles are important for the maturation of the egg, but they do not produce progesterone after ovulation; that function is specifically taken over by the corpus luteum. The ovarian cortex is the outer layer of the ovary that contains the follicles and does not directly produce hormones like progesterone. Thus, the optimal choice is the corpus luteum, as it is directly responsible for the production of this vital hormone during the luteal phase of the menstrual cycle.