Question

Nucleoprotein gave most probably the first sign of
(a)Life
(b)Amino acid
(c)Soil
(d)Sugar

Answer 1

Hint: Nucleoprotein molecules were formed by the union of nucleic acid and protein molecules. These nucleoprotein particles were described as free-living genes. The transformation of organic molecules like nucleic acids as genetic material and some others as enzymes marked an important stage in the chemical origin of life on earth.

Complete answer:
The Abiogenesis of complex organic compounds in the primitive sea was followed by the formation of large spherical colloidal aggregates of macromolecules. The ability of protein molecules to come together and form complexes was very significant in the formation of colloidal systems. Within the colloidal system, the coalescence of particles increased very much. As a result, hydrophilic colloids separated out from the main body and got enveloped by a shell of water molecules. Such clusters of organic molecules covered by water are called coacervates. The coacervates that remain suspended as droplets in seawater. Coacervates served as a site for synthesis of the first RNA by different combinations of pyrimidine-sugar–phosphate and purine-sugar-phosphate. Similarly, polymerization of amino acids formed proteins which took over the catalytic function. The association of proteins and nucleic acids formed self-replicating nucleoproteins which served as genetic material and thus marked the origin of life. Formation of nucleoproteins and surface membrane transformed the nonliving coacervates into first living cells, the protocells.

Additional Information: -The theory of chemical evolution holds that evolution of matter first into organic compounds, then into organic compounds, still further into primitive forms of life, and finally into higher forms of life are not separate phenomena, but the successive stages of a continuous process.
-Organic compounds were formed on the earth surface much before life arose and life evolved from them in seawater at a later stage.
-The chemical evolution of life is believed to have completed in three stages.
So, the correct answer is 'Life'

Note: -During the first stage of organic evolution, simple macromolecules were formed from certain primary constituents.
-In the second stage, complex macromolecules were formed by the condensation polymerization and oxidation-reduction of these macromolecules.
-During the third stage, all kinds of organic molecules got uniquely organized into a living system.