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REPRODUCTION 



Zygote of Parental Generation 



Early Ma/e Germ • cells 

 Spermatogonia 



Germ - cells — Potentially Immortal 

 "Germplasm'^ 



II. Maturation Division 



Fig. 113.— Diagram of maturation in male germ cells, spermatogenesis, 

 showing eight paired chromosomes and a single "X " or se.x chromosome. 



The oosperm or zygote, which is the fertilized ovum, with its eight paired chromosomes, 

 the autosomes, and a single "X" chromosome, is represented by the upper circle. Such 

 a zygote produces by mitotic cell division, as shown schematically on the left, all the body 

 cells or somatoplasm. The zygote also gives rise to the germ cells or germplasm, as shown 



