Page 28 - Miracles in Our Bodies

tem has a much more comprehensive sys-
tem than kilometres of motorways, which

have many crossroads and separate carriageways

for vehicles travelling in opposite directions. Just as vehi-

cles move from one place to another on motorways, elec-

trical nerve impulses are transmitted along the network

of nerves in our body. These impulses convey messages

from one region to another.
These impulses move in your body much faster than

you can imagine. An electrical stimulus sets out from

your brain, for instance, when you want to flex your arm.

During this complicated journey, the stimulus first stops

by the spinal cord. Thence it proceeds towards the organ

concerned, to which the message should be conveyed.

Your arm muscle contracts as a whole and you bend your

arm at the elbow. This series of ac-

tions takes place in a mere thou-
sandth of a second. Considering

that it takes approximately a