What is an ovum like ?

The ovum is a round egg laid by the ovaries. Although only tiny, it is 100 times bigger than a sperm cell. Girls already have a stock of ova when they are born. But they are only half formed. At the onset of puberty, they begin to mature one at a time. When an ovum is ready, it works its way out of the ovary and descends the Fallopian tube. This monthly process is called ovulation.