1. 



SPIRAL MOLECULAR STRUCTURES 

 THE BASIS OE LIFE. 



Introduction. 



Thoro arc certain iDiological proc3GSGS such 

 as growth, va,riation, and reproduction, which are 

 exhibited by 3V :ry living organism, regardless of 

 its rank in the plant or animal kingdom. These 

 processes establish in nature a sharp line of 

 demarcation between living and ncn-living things, 

 since none of the phenomena of physics or chemistry 

 exhibit anything that is similar or analogous to 

 these fundamental life processes. 



Biological grov;th involves not only the 

 accretion of tissue-building material, but also 

 many remarkable chemical transformations which 

 take place during metabolism, as well as the 

 dev elopmierit, in m.ost cases, of highly complex and 

 heterogeneous structures. The nearest approach to 

 this in the inorganic world is the growth of crystals, 

 but crystal growth produces neither the remarkable 

 chemical transformations nor the complex structures 

 which often result from biological growth, not to 

 mention several minor differences such as the 

 polyhedral form of crystals as distinguished from 

 the rounded form of most living organisms, and 

 the hardness of crystals as distinguished from the 

 softness of most living tissues. The differences 

 betv^een crystal growth and biological growth are 

 so manifest that it seems hardly fair to assign 

 them to the sam.e category, and much less to pro- 

 pose the one as an explanation for the other. 



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