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Constantine Sorokin 



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Fig. 3~Time course of photosynthetic gas exchange 

 (in relative units) in small and large Chlorella 

 cells separated from a nonsynchronized suspension by 

 fractional centrifugation. 



Growth under the described conditions (2) is negligible or 

 absent. The importance of maintaining growth conditions has been 

 generally disregarded in photosynthetic investigations. However, 

 growth activity is a reliable indicator of the direction and rate 

 of metabolic turnover. Catabolic activity is much stronger and 

 anabolic orocesses are comparatively weak in nongrowing 

 cells Ud), Enzyme proteins in nongrowing cells undergo fast 

 degradation, products of degradation accumulate, and the size of 

 the active part of the metabolic apparatus is reduced to a 

 minimum. 



