Define arrow. arrow synonyms, arrow pronunciation, arrow translation, English dictionary definition of arrow. n. 1. A missile having a straight thin shaft with a pointed head at one end and often flight-stabilizing vanes at the other, meant to be shot from a bow.
FSH stimulates the growth and recruitment of immature ovarian follicles in the ovary. In early (small) antral follicles, FSH is the major survival factor that rescues the small antral follicles (2â5 mm in diameter for humans) from apoptosis (programmed death of the somatic cells of the follicle and oocyte).
FSH secretion begins to rise in the last few days of the previous menstrual cycle, [unreliable medical source?] and is highest and most important during the first week of the follicular phase. The rise in FSH levels recruits five to seven tertiary-stage ovarian follicles (this stage follicle is also known as a Graafian follicle or antral follicle) for entry into the menstrual cycle.