50 Can Science Explain Life? 



nine and ornithine, then a representative portion 

 thereof will have the following empirical f ormnla : 



C 9 H 1 oN 3 3 , 



and the following percentage composition: 



Carbon Hydrogen Nitrogen Oxygen 

 51.5 5.7 20.0 22.8 



Another possible configuration is that shown 

 in Fig. 8. This is suggested by the molecular 

 structure of leucine and will have the following 

 empirical formula : 



C^H^NoO,,, 



and the following percentage composition : 



Carbon Hydrogen Nitrogen Oxygen 

 51.0 6.7 19.8 22.5 



Although no theoretical basis can be given for 

 the complex shown in Fig. 8, yet it agrees fairly 

 well with the percentage elementary composition 

 of proteins as found experimentally, and also 

 illustrates the branching at the gamma carbon 

 atom which occurs in leucine, phenylalanine, and 

 tyrosine. This complex can be altered in various 

 ways by changing the connections of the carbon 

 atoms with one another, but the percentage ele- 

 mentary composition will remain approximately 



