Page 91 - The Miracle of Electricity in the Body

Adnan Oktar (Harun Yahya) 89

the SA node speeds up since the tissues need the heart to pump more
blood. In this way, the sympathetic nerves raise the blood pressure by
narrowing the blood vessels, and the adrenaline glands over the kidneys
release the hormones adrenaline and noradrenalin, which increase the

speed of the heartbeat. The hormone thyroxin released by the thyroid
gland affects the workings of the heart by speeding the metabolism. 59
The heartbeat can rise to five times its resting level.
The sympathetic nerves speed up the heart like the throttle in an au-
tomobile. When the parasympathetic system is needed, it can slow the
heartbeat to 40 beats a minute by easing the force with which the heart
60
muscles contract. When they detect that the blood pressure has risen,
receptors in the arteries stimulate the brain by means of the parasympa-
thetic nerves to release the chemical known as acetylcholine. Blood ves-
sels in the heart expand, and thus pressure falls. If the blood vessels car-
rying clean arterial blood were not wide enough, they might tear and
rupture. The skull might then fill with blood as in a stroke, and the indi-
vidual be crippled by lack of blood reaching the brain.
But how does this assortment of cells know when to beat, and how
fast? Who tells them to adjust their speed? And how did they acquire the
consciousness with which to carry out such a vital function? How and
by whom is the decision to accelerate or decelerate taken? In the human
body, there is such perfect regulation and such a network of data-ex-
change that no artificial processing network can begin to compare with
it. This system functions without your knowledge, even at this very mo-
ment, showing that it is the product of a superior Intellect and
Knowledge. These belong to our Lord; Who is capable of creating what-
ever He wishes.
Whenever you do something that requires effort, the muscles
around the veins accelerate the flow of blood returning to the lungs. This
means that more blood flows to the right atrium in the heart. At this in-
stant, the muscles contract. The central nervous system transmits the
nerve signals that form as a result of this tension to the medulla oblon-
gata. The medulla analyzes these data and sends a command to the