Query: Is there any cell or bone of fibre that remains
in your body from birth until death?
You are born with your full complement of neurons, which are
the cells of the brain. Loss of a neuron is irrevocable, hence the devastating
effects of a stroke. Recovery of function after stroke results not from growth
of replacement neurons, but from a rewiring of the connections of the brain
demonstrating the superb plasticity of the most complicated object in the
universe.
On the other hand, the constituents of every cell, including
every neuron, are constantly being replenished. Thus you die with different
atoms, molecules, amino acids, proteins etc. throughout your body than you
started with. What keeps the entire body form intact even after every piece is
replaces is one of the great unanswered questions of biology.
Ralph Siegel, Ph.D.
Center for Molecular and Behavioral
Neuroscience
Rutgers University
197 University Avenue
Newark NJ
07102