Page 83 - For Men of Understanding

pumps, each of which has its own ventricle and atrium. This separation also
divides our circulatory system into two. The right side of the heart sends blood
with a relatively lower pressure to the lungs and the left side pumps blood with
a higher pressure to the whole body. This pressure regulation is very impor-
tant, because if the blood sent to the lungs were pumped with the same pres-
sure as the blood sent out around the body, the lungs would be crushed, being
unable to stand this pressure. The perfect balance in the heart does not permit
such a problem to occur in the lungs, because the heart is flawlessly designed.
It provides for the transportation of many needed materials to the
organs: Clean blood coming from the heart is transmitted to the tissues by the
aorta and oxygen is carried to the tissues by the vessels that reach all the cells.
During its circulation in the capillaries, blood distributes substances other than
oxygen such as hormones, food and other kind of nutrients to the tissues.
It has valves arranging the direction of bloodstream and working in
perfect harmony: In the heart, there are valves in the mouth of each cham-
ber that prevent the blood from flowing in the reverse direction. These valves
between the atria and ventricles are made of fibrous tissues and held by very
thin muscles. Since excess blood would leak towards the atriums if one of these
muscles stopped functioning, then serious heart disease would occur that
would cause even death. We come across with such a condition only in cases
of disease. A contrary condition never occurs.
It pumps the required amount of blood depending on changing con-
ditions: The amount of blood pumped by the heart changes according to the
needs of the body. Under normal conditions, the heart beats 70 times a minute.
While doing strenuous exercise, during which the muscles need more oxygen,
the heart increases the amount of blood it pumps and raises its pace to 180
times per minute. What would happen if this were not so? If the heart were to
work at a normal pace when the body needed more energy, the balance would
be harmed and the body would be injured. However, no such thing occurs
because of the perfect structure of the heart. Without making us obliged to
engage in its regulation, the heart regulates the amount of blood to be pumped.
It functions away from our control, yet, exactly as it should: The
amount of blood to be pumped by the heart is controlled by a special nervous
system. Whether we are asleep or awake, our nervous system by itself regu-
lates the amount of blood to be pumped and the speed of pumping. The struc-

ture of the heart - that regulates without any intervention as to where, when
and how blood is needed - is flawless. Since the heart could not have formed
this system on its own, or this perfect system could not have formed by coin-
cidence, the heart is created. Allah, Who has infinite knowledge, designed it in

The Human Being 81