It is important to note that the female ovary is not only the female gonad, which contains the supply of germ cells needed to form the next generation, but it is also the female reproductive gland, which regulates many aspects of female development and physiology.All-female mammals, like all other female vertebrates, are endowed with ovaries. These are the organs that are responsible for egg production. Female reproductive organs in therian mammals are also distinct from those in other vertebrates in that they contain two additional reproductive structures.