500 - Heredity and Evolution 



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Fig. 26-22. Cross of white- 

 eyed female and red-eyed 

 male; Fj inbred. (Adapted 

 from Morgan.) 



— tend to produce offspring that are geneti- nity for am recombination of genetic traits, 



cally identical. All the cells of the offspring This stability of asexual inheritance is of 



are derived entirely by mitosis from the cells great advantage in the propagation of com- 



of the parents; and the mitotic type of cell mercially valuable plants — such as fruit trees 



division operates to perpetuate the existing and potatoes. Any cutting or grafting derived 



combination of genes affording no opportu- from a valuable stock can be relied upon to 



