CELLULAR GROWTH 



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erally means an increase in cell number. Growth in size of cells without cell 

 division may be obtained by specifically inhibiting the process of cell division 

 without interfering with growth. This situation results with some of the 

 mustard gas derivatives, which prevent the cell from dividing but do not in- 

 terfere with the synthesis of protoplasm. As a result, the cell becomes very 

 large without ever dividing. 



Cellular growth 



Growth within the cell is the basic problem that underlies growth of the 

 organism as a whole. In cellular growth it is not the division of the cell, or 

 the separation of the chromosomes, or even the division of the various parts 

 of the cell that is important. All this division is merely the end result of the 

 more important process of reduplication of the chemical constituents of the 

 cell. Before attacking this problem it is necessary to point out one essential 

 concept. This is represented in chart form. 



H + / ^± G 



oo oo 



an infinite series results. 



In the cell the synthesis of any compound, such as a protein or any other 

 large molecule, takes place through the combination of smaller molecules. 

 Let us assume that two molecules, A and B, unite to form C, a larger mole- 

 cule. In order to bring about this reaction an enzyme, which we may call D, 

 is necessary. Any synthesis in the cell in its simplest form would then be repre- 

 sented by the reaction A + B -> C, a reaction catalyzed by an enzvme, D. For 



