RESPIRATION OF PLANTS 



87 



Respiration is closely connected with growth; therefore, the 

 greater the energy of growth the higher is the respiratory rate. 

 Rapidly growing organs, whose cells are rich in protoplasm, often 

 respire more intensely than do animals. Man, for instance, 



Fig. 19. — Warburg's ap- 

 paratus for the study of 

 respiration of plants. A, 

 receptacle for the respiring 

 parts; B, manometer pressure 

 gauge; C, adjusting valve. 



Fig. 20.— Flask for the 

 study of increase in tem- 

 perature induced by 

 respiration of germinat- 

 ing seeds {after Ganong). 



produces in 24 hr. a quantity of carbon dioxide weighing about 

 1.2 per cent of his body. The respiration of germinating seeds 

 at a temperature of 37°C. is of the same intensity. Still greater 

 is the respiration of molds, which produce as much as 6 or even 

 10 per cent of carbon dioxide in 24 hr. per unit weight. 



