CHAPTER III 



Biological Death and Sexual Reproduction 



HOW CONJUGATION DEFEATS DECAY TOWARDS 



EQUILIBRIUM 



In some of the more complex unicellular organisms, 

 reproduction by cell division takes place for many gen- 

 erations, but after some period of time the daughter 

 cells appear to lose vigor, growth and the rate of fis- 

 sion slows down. However, if at such a point, conjuga- 

 tion takes place between two such cells, the organisms 

 are invogorated and become able to subdivide for 

 many new generations. 



Why, one may ask, does the attenuation of vigor take 

 place in some unicellular organisms after a number of 

 generations? Why can some species get along without 

 it? Why does conjugation invogorate? Why does it 

 seem to take place to a greater extent in the more com- 

 plex unicellular organisms and usually become a neces- 

 sity in the most complex forms? Why is a similar cell 

 fusion process the mechanism used in the sexual re- 



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