Ovum is the reproductive cell in the female body of most anisogamous organisms i.e the organisms that reproduce sexually and have larger female gamete and smaller male gamete.
It has a diameter of about 0.1 mm.
It is large enough that can be seen without the aid of a microscope.
Female gonads (ovaries) are the sex glands of female vertebrates that generate eggs. Mammalian ova are present at birth and mature during the oogenesis process.