long-chain molecules like DNA from “amino acid soup” is not straightforward. In addition to the amino acids in the miller-Urey experiment there were high concentrations of chemicals that would have prevented the transformation from short chain (monomers) to long chain molecules (polymers). An equally significant challenge to the theory is how the relatively simple amino acids become complex long chain molecules in water. This is because in a water environment the long chain molecules would favour reaction with water (hydrolysis) to break down into their constituent small molecules (monomers) instead of the loss of water (condensation) for turning individual monomers into polymers. So, natural production of DNA from amino acids in water is chemically impossible.
Another blow for spontaneous generation is in the area of chirality.
A chiral molecule lacks an internal plane of symmetry and its mirror image cannot be superimposed on it. The most frequent cause of chirality in molecules is the presence of a carbon atom where the adjoining atoms are not symmetrical. A chiral molecule can exist in two different forms, distinguished by the direction they rotate polarised light – either clockwise or anti-clockwise. These “optical isomers” have been called left-handed and right-handed.
Two optical isomers of a generic amino acid, from the Wikipedia:
To take a well-known example, let’s look at Glucose and Fructose. These have an identical makeup of atoms within each molecule, but they are opposite optical isomers.
Fructose is an
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