Our sense organs 45

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types of the amino acids in the protein
chains) could be obtained? In a process of
trial and error of various sequences, most of
the combinations would not transport
enough oxygen, which would be lethal. Thus
an evolutionary process of “gradually
approaching” the right combination is
excluded.
Even if somehow the right molecule could be
synthesized to provide for the needs of two
of these stages, death would be certain (and
the evolutionary experiment would end), if
an inappropriate hemoglobin were utilized in
the third stage.
For each of these three stages, essentially
different biological machinery is required. At
the right time, the production has to switch
from the ε chain to the γ chain, and then a
third time to the β chain. How could the
complex machinery necessary to control this
production sequence itself arise?
The only reasonable answer, and the obvious one,
is that everything must have been present and
fully functional from the start, in the DNA coding
of the first human beings—conceived and
planned by a wise Creator.
Leucocytes: The leucocytes, also known as white
blood cells or white blood corpuscles, are much
less abundant than the erythrocytes. There are
only between 4,000 and 10,000 of them in one
mm 3 , and their number is variable. They increase
after a meal or after physical activity. There are
morphologically different kinds of leucocytes;
their purpose is to defend the body against
intruders, each in its own particular way, and to
defend it to the death, as it were. They die by the
millions wherever there is a point of entry for
infection. There are about six thousand million
white corpuscles in every litre of blood, one for
every 600 to 1,000 red blood cells. In contrast to
the latter, the leucocytes are complete cells having
a nucleus as well as organelles. They are also
known as granulocytes, because in large concentrations
the blood plasma appears to be granular.
Five types can be distinguished, three according
to their ability to be stained. Sixty per cent of the
leucocytes are neutrophilic granulocytes (Greek
philos = friend; they are readily stained by neutral
dyes), five per cent are eosinophilic (Greek
eos = the rosiness of dawn; eosin is a red dye
used for microscopic analysis), and two per cent
are basophilic (they can be stained with basic
dyes). The remaining two kinds of white blood
cells are the lymphocytes (30 %) and the monocytes
(3 %).
The leucocyte army is an impressive team of
specialists. While half of them are patrolling
within the blood, the others are on external duty,
guarding the tissues. Bacteria, viruses, fungi and
parasites continually enter our bodies through
breaches of the skin, in the air we breathe, and
from food in the alimentary canal. They are
recognised as enemies, and, when located, the
army goes into action. The basophilic granulocytes
and the lymphocytes fire chemical weapons
at them. Next on the scene are the neutrophils,
the eosinophils, and the monocytes. They individually
surround the intruders and absorb and
digest them. Remarkably, this secret army is able
to clearly distinguish between friend and foe,
between the body’s own substances and foreign
matter.
Thrombocytes: A healthy adult has between
150,000 and 350,000 platelets in a cubic mm of
blood. These thrombocytes have no nucleus, they
are flat, and are irregularly rounded in shape.
They measure between 1 and 4 µm in length,
with a thickness of 0.5 – 0.75 µm, and comprise
cell fragments enclosed in a membrane. Continuously
replenished by the bone marrow, their
average lifespan is between 5 and 11 days. They
are normally inactive, but can be activated by
contact with e.g. roughened surfaces, such as
when a blood vessel is cut or injured, and by certain
blood coagulation factors. When activated,
they are able to release substances necessary for
blood clotting. When blood loss commences
through injury, many platelets accumulating
together form a mass which “plugs” the defect.
In the process, they disintegrate, releasing substances
that trigger off coagulation.
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