734 



PART IV. — THE PHYSIOLOGY OF PLANTS. 



Plant possessing Chlorophyll. 



Income. 

 I. Matter. 



Food; viz. 



Inorganic salts. 

 Carbon dioxide. 

 Water. 

 Free oxygen. 



Expenditure. 

 1. Matter. 



a. Accumulated. 



Organic substance of tissues 

 (protoplasm, cell - walls, 

 etc.). 

 Reserve materials (starch, 

 sugar, fats, proteids, etc.). 

 Unexcreted organic waste- 

 products (tannins, alka- 

 loids, acids, etc.). 

 Mineral matter of ash. 

 6. Dissipated. 



Carbon dioxide") in respira- 

 Water ) tion. 



Free oxygen (evolved by green 



parts in light). 

 Incidental losses (reproduc- 

 tion, etc.) 

 II. Energy. 



a. Accumulated. 



Potential energy of the 

 accumulated organic sub- 

 stance (see above). 

 6. Dissipated. 

 Heat. 



Light (in some cases). 

 Movement (including growth) . 

 Potential energy (in connex- 

 ion with the incidental 

 losses of organic substance, 

 as above). 



In the case of plants which do not possess chlorophyll, the account must be 

 altered thus : — 



II, Energy. 

 Heat. 



Light (absorbed by chloro- 

 phyll). 



Income. 

 1. Matter. 



Food; viz. 



Inorganic Salts. 

 Organic matter. 

 Water. 

 Free oxygen (in most cases). 

 II. Energy. 

 Heat. 



Potential energy of organic 

 food. 



Expenditure. 

 Same as in plant possessing 

 chlorophyll, except that no 

 free oxygen is given off. 



