The Biochemical Function of Cells 401 



there occurred a correlation of biochemical functions with particular structures. 

 In this sense one may speak of the absolute meaning of the correlation of bio- 

 chemical functions with structures, for wherever there is life in any of its forms, 

 there one may find heterogeneity and, in one form or another, a spatial arrange- 

 ment of biochemical processes and functions leading to the separation of 

 individual processes in close contact with others. 



The investigations of recent years have revealed some general laws of the 

 spatial arrangement of biochemical functions in the living cell. However, these 

 rules are different for different forms of Uving things ; in other words, the actual 

 correlation of biochemical processes and functions is not always of the same type. 

 There is no single plan of arrangement of functions applicable to all living things 

 just as there is no uniform structural formation of all living things. 



In the course of evolution there was a continual alteration and development 

 of the protoplasmic structures towards greater differentiation and specialization. 

 This alteration took place in the whole tmit of form and function. 



The development of biochemical fimction took place at the same time as the 

 structural organization became more complicated. The increase in the complexity 

 of the structural organization, or the appearance of new structural elements, 

 took place on the basis of laws of chemical reaction which had already been 

 established. However, at a particular stage, the structural organization, in the 

 course of its stabilization, itself created the necessary conditions for the appear- 

 ance of a new dynamism and direction in the chemical mechanism of the earliest 

 forms of life. The evidence of the biochemical evolution of both animals and 

 plants is in favour of this idea, 



A similar hypothesis allows the possibility that the correlation of a biochemical 

 function with a particular structural organization arose during the process of 

 evolution and is adaptive in nature. Unfortunately we have not enough factual 

 evidence, but there are isolated facts which indicate the possibility that the 

 chemical mechanism of reactions of a uniform type might have become more 

 complicated during the phylogenetic development of the organism. For example, 

 the acyl-coenzyme A system is known to function in both bacteria and animals. 

 The way in which this system is used is, however, different in the two groups. 

 Bacteria split acyl-coenzyme A by means of phosphate, with the formation of 

 acyl phosphate and coenzyme A. In animal tissues mineral phosphate is com- 

 bined with the coenzyme part of the complex of acyl-coenzyme A. The acyl 

 group is later set free in the form of the acid. 



Investigation of the biochemical properties of the intracellular organoids of 

 various phylogenetic groups of organisms is of great importance for revealing 

 the genesis of intracellular structures. 



At present an increase in the depth of our knowledge of the biochemical 

 functions of hving cells is only possible by adopting a different approach to each 

 particular structural formation of cells. It has now become evident that some of 

 the ideas which were put forward on the basis of an overall evaluation of the 

 biochemical activity of the organism and of the cell as a whole require to be 

 made more precise. We are fully justified in speaking of the biochemical diversity 

 of quality of the structures of cells in the sense that each structure has a particular 

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