An ovum ( plural: ova ) is the female gamete. It is the largest single cell in the body. During the development of a female foetus, all the ova that she will ever have in her life are formed. Stem cells in the ovaries differentiate and undergo the first stages of meiosis. The genetic material is reduced by half, but the final cell division remains incomplete. The ova may remain suspended at this stage of development for up to fifty years, but even before she is born, many of these immature ova will have become redundant. After she has reached puberty each month, under the influence of Follicle stimulating hormone (FSH) and oestrogen, a single ovum matures in one of the woman’s ovaries within a specialised structure call a Graafian follicle. Meiosis is completed and the ovum is released into the Fallopian tube in a process called ovulation.
Using the diagram above, print off and label the visible structures on the photomicrograph of a human egg below. Note that the cumulus cells have been removed.
The sperm cell