Answer:
bacteria, archaea, eukaryota
Both plant and animal development is seeded in the perspective that a cell divides itself to form a tissue and tissues grouped will become an organ and the organism itself. The cell hierarchial model is followed in the development in both of these diverse however seemingly similar organisms.
Random fertilization allows random combination of genetic information, which helps synthesize genetically unique gametes. The fusion of a unique sperm together with a unique egg can introduce further variation.