The embryo gets embedded in the wall of the uterus. The uterus will be lined by a wall. This wall then develops into placenta which becomes the source of nutrition and exchange of gases and waste materials between the body of the mother as well as the foetus. The embryo continues to develop in the uterus. It gradually develops body parts such as hands, legs, head, eyes, ears, etc. The stage of the embryo in which all the body parts can be identified is called a foetus.