The ability of an organism to regenerate its lost body parts is called regeneration. When a part of the body of an organism gets damaged or crushed, a new identical part starts to develop from the point of damage some time after. Thus, all newly formed portions grow into fully functional organs or body parts lost previously.

regeneration in planariaExamples of organisms that reproduce through this method include Planaria, Star fish, Sponge and Hydra. Some organisms like filamentous algae multiply through this method. The filaments of algae break and develop into a new alga that acts independently. This is known as Fragmentation.