Ask A Scientist Molecular Biology Archive

name         Phillip G.
status       educator
age          20s

Question -   Neurons send out either excitatory post synaptic
potentials (EPSPs) or inhibitory ones (IPSPs).  If a neuron either
excites or inhibits, why is it necessary for the body to have so many
neurotransmitters when it seems two would do the job just as efficiently?
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Part of the confusion you have, I am fairly certain, is in your thinking
that the system is anywhere as simple as most textbooks indicate.  A single
neuron may have hundreds to thousands of other nerve endings impinging on
it.  If you think of all the possible messages the system has evolved to
transmit and handle it is staggering.  Also remember that we do not
understand how the system really processes complex messages...listening to a
symphony while walking on a busy street and eating a donut, for example. One
thing is for certain, it has very little in common with human-made machines
trying to mimic the system in part...the computer on which I am typing for
example or a robot that does house chores.

Peter Faletra Ph.D.
Assistant Director
Science Education
Office of Science
Department of Energy
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