102 



Does Light Inhibit the Respiration of Green Cells ? 



No. III. Gas phase 5% C0 2 in air, respiration overcompensated several-fold by white light. 



Vessel 3 



20' white light 39 mm. 



20' white + red light \- 48 mm. 



Vessel 5 



20' red light action 



9 mm. 



26 mm. 3 

 26 mm. 3 



CQ 2 



Oo 



1.0 



It will be observed that the oxygen consumption in the dark in Nos. I and II is essentially the same 

 (about 42 mm. 3 /20'). This means that the C0 2 pressures used did not influence respiration, and 

 that the CO2 pressure required to obtain maximum respiration is below that required for effective 

 photosynthesis, where CO2 is required as Substrate and not merely catalytically. 



