Cell fusionCell fusion is an important cellular process in which several uninucleate cells (cells with a single nucleus) combine to form a multinucleate cell, known as a syncytium. Cell fusion occurs during differentiation of myoblasts, osteoclasts and trophoblasts, during embryogenesis, and morphogenesis. Cell fusion is a necessary event in the maturation of cells so that they maintain their specific functions throughout growth. In 1847 Theodore Schwann expanded upon the theory that all living organisms are composed of cells when he added to it that discrete cells are the basis of life.