Regeneration (biology)

Regeneration is the ability to restore lost or damaged tissues, organs or limbs. It is a common feature in invertebrates, but far more limited in most vertebrates. Nevertheless, even humans possess some degree of regeneration ability. Children under 6 years of age are capable of regenerating lost fingertips and the human liver retains its ability to regenerate throughout a person's lifetime.

Related Topics:
Invertebrate - Vertebrate - Fingertip - Liver

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Aside from being used to generally describe any number of specific healing processes, regeneration also is a specific method of healing that is noted for its ability to regrow lost limbs, severed nerve connections, and other wounds. This is present in some animals such as the newt, hydra, and a type of mouse. http://www.wistar.upenn.edu/research_facilities/heberkatz/research.htm http://jaxmice.jax.org/jaxmice-cgi/jaxmicedb.cgi?objtype=pricedetail&stock=002983. With the exception of the MRL mice, mammals do not in general have the ability to regenerate. If the processes behind regeneration are fully understood, it is believed this would lead to better treatment for individuals with nerve injuries, broken backs, paralysis, and missing limbs.

Related Topics:
Newt - Hydra - Mouse

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Regeneration of a lost limb occurs in two major steps, first de-differentiation of adult cells into a stem cell state similar to embryonic cells and second, development of these cells into new tissue more or less the same way it developed the first time. Some animals like planarians instead keep clusters of non-differentiated cells within their bodies, which migrate to the parts of the body that need healing.

Related Topics:
Differentiation - Stem cell - Development - Planarian

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