BIOSYNTHESIS OF PROTEINS qSq 



adaptation to its biological function, such ' purposeful ' 

 structure, is also characteristic of the nucleic acids of present- 

 day organisms and its origin by chance is as impossible as 

 the chance assembly from its elements of a factory capable 

 of turning out any particular product. 



The third and final point is that, even if we admit for a 

 minute the possibility that in the primaeval soup of the 

 ocean there might have arisen by chance molecular matrices 

 which could reproduce themselves incessantly, even then life 

 could not arise on this basis. In such a case the matrix would 

 continually produce nothing but molecules exactly like itself 

 and the primary organic material would simply be converted 

 into uniform layers of nucleic acids or deposits similar to the 

 ' mineral formations ' of crystallised organic materials. 



The molecule of nucleic acid in contemporary living 

 organisms is not an independent ' living molecule ', it is only 

 a part of living protoplasm, an organ of that protoplasm 

 subserving a function necessary for life. Thus, all that we 

 have already said about the origin of proteins or enzymes 

 applies equally to nucleic acids. 



Contemporary scientists are also quite right in supposing 

 that the development of matter proceeded from simpler to 

 more complicated systems. Nevertheless, although the separ- 

 ate organs, such as an arm or an eye, are simpler than the 

 whole organism, we should not assume, like Empedocles, 

 that higher living things developed by the aggregation of 

 separate organs. Danvin has shown us the true way in which 

 these living organisms arose. This way is through the evolu- 

 tion of more simply organised things, the evolution of com- 

 plete systems brought about by natural selection. 



Similarly it would be wrong to suppose that there first 

 arose proteins, nucleic acids and the other complicated 

 substances found in protoplasm, which had intramolecular 

 structures which were extremely well and efficiently adapted 

 to the performance of particular biological functions, and 

 that living protoplasm itself arose as the result of a combina- 

 tion of these substances. 



All that we can expect from the relatively simple thermo- 

 dynamic and kinetic laws which prevailed on the surface of 

 the primaeval Earth is that they should explain the formation 



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