Theory of Chemical/Biochemical evolution/Modern theory of the origin of life/Operin-Haldane theory of the origin of life/ Materialistic Theory or Physico-chemical (Part -2)

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Theory of Chemical/Biochemical evolution/Modern theory of origin of life/Operin-Haldane theory of origin of life/ Materialistic Theory or Physico-chemical Theory:

C) Synthesis of a simple organic compound: Next step is the formation of macromolecules. When the temperature of the earth gradually cooled down (1000 C) then the highly reactive free radicals CH and CH2 condensed to form a variety of saturated and unsaturated hydrocarbon.

Due to the condensation, polymerization, reduction, and oxidation of Hydrocarbon, ammonia, and water, several organic molecules like monosaccharides, amino acids, nitrogenous organic bases (purines and pyrimidines), fatty acids and glycerol, etc. were formed.

H2O + CH4 ⟶ Sugar/Fatty Acid/Glycerol 

H2O + NH3 + CH4 ⟶ Amino Acid/Nitrogen Base

The synthesis of carbohydrates, fats, amino acids, and other complex organic compounds presumably took place in the sea. J. B. S. Haldane described this mixture of seawater as “hot dilute soup or primitive broth”.

D) Formation of complex organic compounds The simple organic compounds were polymerized to form complex organic compounds like polysaccharides (sugar), proteins, nucleoproteins, polypeptides, fats, lipids, etc.

Sugar + Sugar ⟶ Starch/Glycogen/Cellulose etc

Fatty Acid + Glycerol ⟶ Fats

Amino Acid + Amino Acid ⟶ Protein

The protein molecules are formed by the polymerization of amino acids (photoprotein). The formation of protein molecules is considered as a landmark in the origin of life. There was a large number of complex organic compounds in ocean remained to unspoil due to the absence of life.

E. Formation of Nucleic acid There was the formation of nucleotides by the combination of sugar, phosphate, purine, and pyrimidine.

Nitrogen Base + Sugar + Phosphoric Acid ⟶ Nucleotides

Nucleotide + Nucleotide ⟶ Nucleic Acid (DNA/RNA)

Nucleotides formed nucleic acid which is the basic component of life. Nucleoproteins appeared in the primitive ocean as self-duplicating systems. Hence, the nucleoproteins once formed, must have steadily increased in the oceanic soup. By virtue of their self-duplicating property, these are capable of performing the hereditary functions. The first sign of self-perpetuating life was thus displayed by the nucleic acids. Thus, life was presumably originated in the ocean, about 3.7 billion years ago.

 Theory of Chemical/Biochemical evolution/Modern theory of the origin of life/Operin-Haldane theory of the origin of life/ Materialistic Theory or Physico-chemical (Part -1) 

Theory of Chemical/Biochemical evolution/Modern theory of the origin of life/Operin-Haldane theory of the origin of life/ Materialistic Theory or Physico-chemical (Part -3)  


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