6 INFLUENCE OF TEMPERATURE ON BIOLOGICAL SYSTEMS 



various constituents, it is clear that one should not expect to encounter 

 spontaneous generation of our critical complex arising from as many as 

 12 elementary compounds. On the other hand, mutations arising from 

 the recombination of two or three fragments ought to be observable as 

 they are. It is, of course, an extremely lively question to ascertain how 

 changes in cell heredity typified by cancer occur. When does cancer come 

 from the addition of some desoxyribonucleic acid from virus-like bodies 

 to the chromosomes, and when does it come from mutation inside the cell? 

 Rate theory typified by equation 3 is applicable in either case and should 

 be an important tool in such studies. It is especially interesting to con- 

 tinue examining fossils to find out whether the amino acids they contain 

 are all of the I form. Chromatographic separations and micro polarimetry 

 facilitate such investigations. It is exceedingly interesting to be certain 

 whether or not the burst of activity from the first optically active self- 

 replicating critical complex really succeeded in slamming the door im- 

 mediately on all competitors. With optically active enzymes once estab- 

 lished, their dynamic stability against Walden inversion arises from the 

 fact that usually inversion of an amino acid ruins the enzyme containing 

 it, and so fatally handicaps the afflicted organism in its race for sur- 

 vival (7). 



Our general explanation of the emergence of optical activity of the 

 enzyme amino acids would be equally cogent were the critical complex 

 some such molecule as desoxyribonucleic acid or an enzyme rather than 

 ribonucleic acid. We have preferred the notion that ribonucleic acid was 

 the critical complex in biogenesis, thinking of it as the most primitive 

 template for proteins because of its wide distribution throughout the 

 cytoplasm. However, additional evidence on this point would be wel- 

 come (6, 8, 9). 



FURTHER EXAMPLES OF CRITICAL COMPLEX THEORY 



As we have seen, the emergence of optically active enzymes ushered in 

 a new epoch. A similar turning point probably occurred in nuclear evo- 

 lution. With the discovery of anti-electrons (positrons) and anti-protons, 

 it is natural to visualize another universe where positive electrons rotate 

 about negative nuclei. This anti-world should be exactly as stable as our 

 own world. Since two such systems would be mutually destructive, it is 

 natural to postulate that in the period when energy first condensed to 

 form matter, the same general type of fluctuations which gave us an 

 i-amino acid world gave us billions of years early ascendancy of our 

 negative electron world over its competitor. Professor Carl J. Christensen 

 called our attention to the parallelism in the arguments required to explain 

 this nuclear case. Finally, the growth of optical enantiomorphs, as of 



