A multicellular organism is one that is constituted by two or more cells which arise from a single cell which multiplies generating an organism. The cells of multicellular organisms aredifferentiated to perform specialized functions and reproduce by mitosis and meiosis.Cellular specialization includes the division of biochemical functions, the specialization of cells for contact with the environment and the separation between somatic cell and germ cell.
Natural selection is a mechanism of evolution. Organisms that are more adapted to their environment and are more likely to survive and pass on the genes that aided their success. This process causes species to change and diverge over time.
