These are excerpts and elaborations from my book "The Nature of Consciousness"
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The Matter of Life Life on Earth is based on
the element carbon. Carbon can bond with oxygen, hydrogen and nitrogen because
of its four valence electrons. Both proteins and nucleic acids (DNA, RNA) are
made of carbon, and energy is stored in the form of carbohydrates. Energy transformations are
linked with the dual processes of oxidation and reduction. Oxidation and
reduction reactions occur in pairs: in
order for a substance to be reduced another substance must be oxidized. When an
atom is oxidized, it loses electrons; and when it is reduced, it gains
electrons. Oxidation is a process by which a carbon atom gains bonds to
(usually) oxygen. Reduction is a
process by which a carbon atom gains bonds to (usually) hydrogen. Molecules
gain oxygen or lose hydrogen in an oxidation reaction; lose oxygen or gain
hydrogen in a reduction reaction. Fritz Lipmann (The metabolic generation and
utilization of phosphate bond energy, 1941)
discovered that Adenosine Triphosphate (ATP), a high-energy phosphate
and therefore a source of readily available energy, and showed that it
constitutes the main fuel for many biochemical
processes and, in particular, is the main energy carrier in cells. He
had basically found the connection between the metabolism and the physics of
biological systems, i.e. the chemical process that makes life possible. Organic molecules are based
on carbon, and energy transactions are based on phosphorus. Oxidation-reduction energy
is pervasive in nature. and (relatively rare) Phosphate-bond energy is
relatively rare in nature. Life owes its existence to the fact that at some point
the two met. Back to the beginning of the chapter "The Evolution of Life: Of Designers and Design" | Back to the index of all chapters |
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