Regeneration is a form
of tissue repair; the restoration
of lost or damaged tissues,
organs or limbs. 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.
It can be seen in the organisms of planaria and starfish.
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 [7].
Human ribs can regenerate
if the periosteum, the membrane
surrounding the rib, is left intact.
For this reason, ribs are used
as a source of bone
in reconstructive surgery.
The Human Liver is one
of the few glands in
the body that has the ability
to regenerate from
as little as 25%
of its tissue.
This is largely due
to the unipotency
of hepatocytes.
Hepatocytes make up
60-80% of the cytoplasmic
mass of the liver.
These cells are involved
in protein synthesis,
protein storage
and transformation
of carbohydrates,
synthesis of cholesterol,
bile salts and phospholipids,
and detoxification,
modification and excretion
of exogenous and endogenous
substances. The hepatocyte
also initiates the formation
and secretion of bile.
