MAMMALIAN CELL GROWTH IN TISSUE CULTLTRE 



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Figure 2. Idiogram of normal human female chromosomes. 



two of the long-recognized and intriguing aspects of the differential 

 vital statistics of the sexes in man appear to have at least a plausible 

 explanation in the structures of the human sex chromosomes. 



While in the first complete analysis of the human karyotype only 

 four satellited chromosomes were described, subsequent study has 

 revealed the existence of another satellited pair (Figure 4), and it is 

 conceivable that still more such structures may exist (Tjio, Puck, and 

 Robinson, 1960 ) . An international study group, assembling in Denver in 

 1960, agreed on a common system of chromosomal nomenclature which 

 is eliminating much of the confusion arising from the different systems 

 that had been used by different workers ( Robinson, 1960 ) . 



