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HUMAN BIOLOGY 



to together as a diplosome. The cytoplasmic material tends 

 to be radially arranged about the diplosome which must be a 

 dynamic center of some kind. 



Fig. 4. Schematic representation of cell division. 



A. Resting cell with diplosome just above nucleus, b. Separation of two 

 centrosomes of diplosome. Spireme formation within nucleus, c. Longitudinal 

 division of spireme, d. Chromosomes formed from each half of spireme arranged 

 on opposite sides of equator, e. Groups of chromosomes migrate apart and 

 lose tiieir distinct outhnes. Groove appears about equator of cell. f. Groove 

 deepens and pinches originally single cell into two. 



B. The first change consists of a concentration of the 

 chromatic substance into a long and tortuous thread or 



