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THE SCIENCE OF BIOLOGY 



Fia. 13. Mitotic or Indirect Cell Division. A, cell with nucleus in resting 

 phase; B, prophase, chromosomes appearing and two centrosomes that 

 have arisen by division of the single centrosome in A now separating with 

 formation of spindle; C, metaphase, chromosomes at equator of fully 

 developed spindle are now split lengthwise; D, anaphase, the separation of 

 the two daughter groups of chromosomes; E, telophase, massing of two 

 daughter groups and division of the cytoplasm; F, completion of the 

 process with return of nucleus to resting phase. (Redrawn with modifica- 

 tions from figures by Agar, "Cytology.") 



