22-25 



THE yEAST CELL 



Fig. 22-7 Growth of Pan- 

 tothenate -Dependent Culture 

 ,2154 in Pantothenate-Free Me- 

 dium. Arrow A indicates the 

 inoculum and arrows B and C 

 the points where rapidly 

 growing mutants were detected. 

 These data are interpreted as . 

 indicating that a change in 

 rate of growth occurred during 

 the "primary" adaptation, and 

 that the yeast cells became 

 adapted to the pantothenate- 

 free medium before mutations 

 to the final "adapted" form 

 occurred. 



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