Regeneration is a Biological process in some living organisms including both plants and animals. Regeneration is an ability to recreate or replace the lost or damaged or amputated parts like limbs, organs or tissues thereby restoring the original function of the particular lost / damaged part.
Regenerative capacity is inversely related to the complexity of the body structure i.e., more complex the structure of an animal less the capacity of regeneration
Ex. Mammals cannot regeneration generate. While organisms like sponges, planarians have an enhanced capacity to regeneration generate;.
The ability of regeneration varies greatly among living things. Plants can regenerate all parts of its from precursor cells, as Trees which is cut off to the ground level , in due course, sprouts starts appearing at the margins of the stump. Then grow on to develop new stems, leaves and flowers.
Coming to the Regeneration in animals, Invertebrates like Sponges, Hydra, Planarian are capable of regenerating entire body from just a conglomeration of their cells. Starfish can regenerate the entire organism from just one arm and the central disk.
In Vertebrates ability of regeneration is found in Amphibians and Reptiles. Amphibians can regeneration a missing tail, legs and even eyes, This remarkable ability is particularly pronounced in the larval stage.