1. Some Scholarly Musings
The Chemistry of Life
Some Scholarly Musings

2. 3 Basic Chemical Concepts
Biomolecules are organic compounds selected for their fitness in performing specific life functions. They are made up of small subunit molecules linked together by covalent bonds. The geometry of the molecules is largely determined by the tetrahedral bonding of the C atom.
H2O is the solvent for living systems; thus, the properties of H2O define how life evolved and is maintained. How biomolecules behave in an aqueous solution is fundamental to understanding the molecular logic of life.
Many weak (non-covalent) interactions, acting cooperatively, stabilize the three-dimensional structures of biological macromolecules and supramolecule complexes, while allowing sufficient flexibility for biological actions.

3. I Wonder Why?
This chart illustrates the not so obvious: the chemical composition of living systems is substantially different than the world from which they sprang. The Periodic Table tells us that there are 92 naturally occurring elements; add another 20 or so that have been created in the laboratory and have fleeting existences. But, all together, only about 30 of the naturally occurring elements are widespread on earth...and barely a half dozen are of central importance to life. So...the question is: how to account for the difference in relative abundance on the earth’s crust vs in living organisms?
Oxygen, for example, is our most abundant element (~50%) and is vital to life; but Si is 2nd most abundant and has little to do with us. Likewise, Al, fourth most abundant, simply is not a part of the fabric of life. On the other hand, C, in 15th place, (<0.05% of earth’s crust), is at the very core of the biomolecular world.
What sets it apart and makes it so vital?

4. Chemical Composition of Living Matter
It is almost exclusively C-based molecules the bond together to form layered structures, like membranes, or chain-like polymers
Building these structures rely on just a few types of chemical reactions and invariably involve a modular design, using just 4 types of molecules: sugars, amino acids, nucleotides & hydrocarbons
Given the aqueous nature of the soup and the almost certain abundance of lipid molecules, spontaneous lipid self-organization into membranous vesicles with an aqueous interior was a likely early event.