1332 



INDUCTION PHENOMENA 



CHAP. ;v.i 



ceding dark period to its level 0.5-1 minute after the beginning of the sub- 

 sequent dark period, when the initial respiration burst has subsided. (This 

 meant assuming, in contrast to Warburg, that the burst was something 

 that happened entirely after the end of illumination, and not the "tail end" 

 of enhanced respiration during the light period.) Brackett et al. used the 



\ r 



nx^AAW t A^'^f*. yK-'X* W*^» 



'** — •--K.v...^ 



4- 



w 



^ 



.11;;^ 



s 



n 



Fig. 33. 6F. Aerobic O2 induction in Chlorella measured potentiometrically in three 

 successive 3 minute light periods with 9 minute dark intervals: dashed line, interpolated 

 respiration; circles, measured points; crosses, points corrected for respiration (after 

 Brackett, Olson and Crickard 1953^). Abscissa, time (min.). Ordinate, rate of oxygen 

 evolution. 



SO interpolated time curve of respiration to correct the measurements of 

 oxygen production during the light period (cf. figs. 33. 6F and 37D.32), and 

 obtained in this way curves showing only the normal negative induction in 

 light. The latter lasted between 10 seconds and 2 minutes, and was fol- 

 lowed by a very steady photosynthesis for the rest of the light period. No 

 evidence of an oxygen burst in the first seconds of illumination is visible on 

 these curves. 



