Multicellular organisms are composed of many cells, which are integrated and independent to various degrees, according to Encyclopædia Britannica. A multicellular organism's development is accompanied by cellular specialization and division of labor. The cells of multicellular organisms become efficient in one process and are dependent on other cells to survive.
The four essential processes by which a multicellular organism is made are by cell proliferation, cell specialization, cell interaction and cell movement. In cell proliferation, many cells are produced from one cell. In cell specialization, cells are created with different characteristics at different positions. In cell interactions, the behavior of one cell is coordinated with its neighbors. In cell movement, the cells are rearranged to form structured tissues and organs.