Question

What is the mature follicle size?

Answer 1

​​The production of a mature female gamete is referred to as oogenesis, which differs from spermatogenesis. Oogenesis begins during the embryonic development stage, when a few million gamete mother cells known as oogonia are created within each foetal ovary; following birth, no more oogonia are formed or added.

Complete answer:
The Graafian follicle is one of the tertiary follicles that grows and matures during the follicular phase. Gonadotropins (LH and FSH) promote follicle development. The preovulatory follicle is $18$ to $23$ mm in diameter.
Each ovarian cycle begins with the maturation of a primary follicle, which begins with the commencement of puberty. Secondary follicles are formed when main follicles are surrounded by extra layers of granulosa cells and a new theca. A fluid-filled hollow antrum emerges between the granulosa and the granulosa cells, indicating that the secondary follicle has transformed into a tertiary follicle.
At adolescence, the primary oocyte within the tertiary follicle matures and expands in size, completing its first meiotic division. An outsized haploid secondary oocyte and a tiny polar cell are formed as a result of an uneven division.
The mature follicle, also known as the Graafian follicle, develops from the tertiary follicle. The Graafian follicle ruptures in the presence of LH hormone, releasing the secondary oocyte growing from the ovary through the process of ovulation. The ruptured follicle left in the ovary after ovulation is converted into the corpus luteum, which secretes mostly progesterone.

Note:
In most cases, alternative ovaries liberate just one ovum per menstrual cycle. In a year, each ovary produces six ova. Human females generate ova over the course of their reproductive lives, which last roughly $35 - 40$ years.