When an
autonomous cyclic reaction system evolved and maintained within a liquid
medium, several other interconnected reaction cycles spontaneously generated
using the chemical components participating in the first reaction cycle.
Similarly, chemical components participating in the secondary reaction cycles,
in turn, initiated more interconnected reaction cycles and, thus, a very
complex process of chemical evolution ensued within the liquid matrix in a
random fashion.
Reaction cycles,
associated with polymerization and de-polymerization of the same or similar
precursor molecules were then become as the regulatory center of all other
cycles, because the same precursor molecules ware associated and dissociated as
necessary to function as a reservoir and provider of the precursor molecules
and thereby preventing depletion and termination of the associated cycles. This
was also required to maintain balance between all of the associated reaction
cycles. As a result, reaction cycles became localized around a center with
highest concentration of the precursor molecules linked together in a polymer
structure.
At a certain
point, in the course of the chemical evolution, huge amount of hydrophobic
molecules appeared through one of the associated branch of reaction cycles.
Those molecules accumulated in the surrounding liquid medium (water) through
hydrophobic interactions (non-polarized hydrocarbon chains in hydrophobic
molecules repel water molecules, accumulate together and create hydrophobic
barrier). As a result, random, free passage of all chemicals became restricted
and all of the reaction cycles became compartmentalized. Such events were
extremely useful for the generation of primitive cellular structures.
Hydrophobic molecules accumulate together and create vesicle like
structures in which chemical reactions are isolated and free passage of
molecules are restricted. Such vesicles create cellular structures and
organelles (nucleus, mitochondria, endoplasmic reticulum, etc) in cytoplasm
where reaction cycles become isolated and compartmentalized.
In such an
organization of molecules, reaction cycles became self-regulated depending on
the availability of participating chemicals. For example, when huge amount of
the hydrophobic molecules were generated and accumulated, the free passage of
molecules in the surrounding medium was restricted and the supply of the
precursor molecules were reduced. As a result, production of the hydrophobic
molecules was slowed down. When production of the hydrophobic molecule was
reduced, integrity of the hydrophobic barrier and restriction to the passage of
chemicals became weak. As a result, precursor molecules along with all other
chemicals readily diffused through the hydrophobic barrier according to their
concentration gradients. On the availability of precursor molecules,
hydrophobic barrier was further strengthened to restrict the passage of
chemicals. Probably, this was the only mechanism to regulate reaction cycles in
the primitive forms of biological system because well-organized biological
membrane with regulatory proteins was not yet evolved.
Probably, this
was the most primitive form of self-regulated biological system with simple
organization of hydrophobic molecules appeared through chemical evolution.
Next, a complex process of biological evolution ensued that gradually improved
the simple organization of molecules into complex unicellular organisms. Finally,
more complex multi-cellular organisms appeared through cellular evolution.
However, the
cycles of chemical reactions and the steps of chemical evolution could be
traced by analyzing all possible reaction steps in water medium involving
simple organic compounds. A detailed reaction pathway could be designed with
the help of chemical engineers, organic chemists, biochemists and
super-computers. Such effort could be useful to explore the detailed mechanism
of chemical evolution towards the origin of more complex biological systems.
Even, it would be possible to reproduce the same reaction pathways within a
suitable liquid matrix in the laboratory condition to observe the course of
chemical evolution in the way to the origin of a primitive form of biological
system. If the complete process is regulated and controlled externally by
manipulating suitable laboratory conditions, primitive form of an artificially
designed organism may even be obtained quickly.
This view is, in
fact, not contradictory to religions. According to religious doctrine, Adam was
sent to the earth, which was already very rich with various types of plant and
animal species evolved through the complex process of evolution. None of the
religious doctrine denies the process of evolution. Because, the evolution was
completely dependent on chemical reactions, the process is not inaccessible to
human investigation. Even, it might be possible for us to artificially design
the biological body of an organism because dealing with substance is not denied
by religious doctrine. Rather, religious statements always encourage us for
scientific investigation to uncover the mystery of the creation to realize the
power of Almighty. In fact, human intelligence is freely accessible throughout
the substantial entities in the physical world but its ability for
investigating the abstract and divine entities is limited. Hence, a pious and
religious minded person should not be anxious about the superior power of
Almighty.