cytology: the study of the cell 151 



themselves, there is no reason to consider that all characteristics in man- 

 physical, physiological, and psychological — are not also controlled by genes 

 lying in the chromosomes. This does not in any way imply that environment 

 does not have an effect in modifying or even suppressing the action of the 

 genes. Environment will not, however, create characteristics for which no 

 genie basis exists. It can merely act upon the gene-induced traits and modify 

 them if it can. All the evidence supports the conclusion that man's traits are 

 induced in the same way and subject to the same external influences as in 

 other forms of life. 



From this brief discussion it is evident that cytology deals with the most 

 fundamental properties of living beings — how the living material is organized 

 and constructed, how it carries on its multitudinous processes, how it is gov- 

 erned, how it reproduces and transmits to successive generations the powers 

 which it possesses. The answer to all the basic riddles of living nature, so 

 far as they are capable of solution, are to be found in the cell, the happy 

 hunting ground of the cytologist. 



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