What is the Difference Between Epimorphosis and Morphallaxis?

Epimorphosis and morphallaxis are two types of tissue or organ regeneration processes observed in animals, primarily in invertebrates. The main differences between these two processes are:

• Cellular Differentiation: In epimorphosis, the majority of regeneration comes from cellular differentiation, while in morphallaxis, the majority of regeneration comes from reorganization or exchange.
• Cell Proliferation: Epimorphosis is characterized by a greater relative degree of cellular proliferation, whereas morphallaxis involves less cellular proliferation.
• Blastema Formation: Epimorphosis is accompanied by the formation of a population of undifferentiated cells called blastema, whereas morphallaxis is not.

Examples of organisms that exhibit epimorphosis include salamanders, annelids, and planarians. In planarians, for instance, neoblasts help in regeneration. On the other hand, morphallaxis is mainly shown by cnidarian hydra. When a hydra is severed into two, the remaining severed sections form two fully functional and independent hydra, with a large majority of regenerated tissue coming from the rearrangement of existing cells.

Comparative Table: Epimorphosis vs Morphallaxis

Epimorphosis and morphallaxis are two types of tissue or organ regeneration processes observed in animals. Here is a table summarizing the differences between them:

Epimorphosis is observed in higher-order species and relies on cellular differentiation for regeneration, while morphallaxis is observed in lower-order species and relies on reorganization or exchange for regeneration.