CHAPTER V 



REPRODUCTION KARYOKINESIS-A VITAL PROCESS- 

 CELL-DIVISIONIS IT MECHANICAL? EXPERIMEN- 

 TAL EMBRYOLOGY 



WE have already seen that one of the leading 

 characteristics of living things is their power to 

 reproduce themselves, to increase and multiply. 

 In the case of the amoeba this process is of the 

 simplest nature, for from the single individual are 

 formed two new members of the race, neither being 

 strictly speaking mother nor daughter. 



In the great majority of cases and in all the 

 higher animals and plants reproduction takes place 

 as the consequence of the fusion of elements derived 

 respectively from the male and the female which 

 combine to form a single cell from which are de- 

 rived, by successive divisions, all the cells, however 

 many and however differentiated from one another 

 of which the adult body is built up. 



In certain cases no remarkable phenomena 

 attend this process of the division of a cell into two 



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