Ask A Scientist© Biology Archive

name         SEAN
status       student
age          20s

Question -   OUR BRAINS SEND ELECTRICAL IMPULSES RIGHT. IS IT
BASICALLY SAME AS NORMAL ELECTRICITY? IS IT LIKE ELECTRICITY FROM
OUTLETS,LIGHTNING..ETC  IS THERE ELECTRICITY ANYWHERE ELSE IN THE HUMAN BODY?
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Hi Sean

Your nerves do not work quite the same way as an electric wire.

Electricity is a movement of charge. In a wire the electrons move to carry
the charge along the wire.

In a nerve the electrical signal moves although no electrical charge
actually moves along the nerve - the signal travels in the form of an
action potential.

The inside of nerve cells normally has a slight negative charge as a result
of the activity of pumps which move charged ions prodominantly out of the
cell. When an electrical charge is placed near a nerve cell it causes gates
in the membrane to open and allow the ions to reenter the cell and
depolarise the membrane near the position where the charge is located. The
depolarisation causes ion channels to open in the membrane a little further
along the nerve (resulting in depolarisation here) and then channels open
in the membrane a little further along...the chain reaction of
depolarisations moves along the nerve until it gets to the end where the
depolarisation causes an appropriate response (such as muscle contraction).

________________________
Cameron Millsom
Trinity Education Centre
University of Melbourne
Parkville, Victoria,  3052,  Australia
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You have nerves in every part of your body and impulses are sent electrically
from the brain to all parts of the body.  It is similar to electricity in
that there is a difference in electrical potential between one area of the
nerve and another.  Nervous transmission is quite complicated to explain
here.  I suggest you find a biology text and read up on the sodium-potassium
pump.  Your heart muscle is also capable of electrical activity.
Van Hoeck
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