2 4 



ZOOLOGY. 

 FIG. 7. 



: "v:-C S P . S ,-^jfej 



''ffil;-' sp - 'i- N 



IMG. 7. Indirect or mitotic division (diagrammatic); A, resting mother nucleus; B, 

 toil stage, with the centrosomes separating; C, D (metaphase), and E, stages in the divi- 

 sion of the chromosomes; F, diastroid (anaphase) stage; G and H show the return 

 of the daughter nuclei to the coil and to the resting condition, and division of the 

 cytoplasm, and the formation of the dividing wall: c, centrospheres; cl, chromatin 

 coil; chr, chromosomes; nu,, nucleus; n, nucleolus; sp, nuclear spindle; w, cell wall. 



Questions on the figure. What structures possessed by the original 

 cell are divided in this process? In what order? Why is this termed 

 "indirect" division? Which is the more common, the direct or the 

 indirect? Can you see any special gain secured by this method? Describe 

 the behavior of the nucleolus and the nuclear membrane by comparing tAis 

 with other figures in reference books. 



