ENERGY TRANSFORMATIONS IN LIVING MATTER 135 



Without disparaging the importance and value of such work 

 of separation of intracellular enzymes, it may, however, be urged 

 that there is in such a view no explanation of the phasic activity 

 of the cell, no taking into account of the action of the living cell 

 in co-ordinating, so to speak, the myriad activities going on within 

 it whereby the whole process is regulated. Such a solution of 

 enzymes compared with a living cell would be like a horde of savage 

 warriors compared to a civilised and disciplined army of soldiers, 

 or a mass of unicellular organisms compared to a highly differentiated 

 mammal. 



There must obviously in the cell be some type of energy con- 

 trolling all this metabolic activity, and this is the rcle played by the 

 biotic energy of the cell. 



VI. The osmotic phenomena of the cell demand for their ex- 

 planation the presence of a type of energy not found elsewhere than 

 in living structures. 



Even in the case of those cells of the body which in form 

 look most like simple membranes, such as the air cells of the lung 

 and the thin endothelial cells of the wall of lymphatic and blood 

 capillaries, it has been clearly shown that the laws of diffusion 

 and osmosis as observed in the case of inert, non-living mem- 

 branes are not obeyed. These structures are not inert membranes, 

 but living cells displaying biotic energy, taking up energy from 

 the plasma in chemical form and using that energy by converting 

 it into volume or osmotic energy, and effecting thereby separation 

 of substances in solution in greater concentration; that is to say, 

 such cells act as energy transformers, the ultimate conversion being 

 from chemical into volume energy. 



Such a change is seen in the secretion of gases both in the 

 swimming bladder of the fish, and, according to Bohr and other 

 observers, in the mammalian lung, where the partial pressure of 

 the carbon dioxide separated in the alveolar air is higher than that 

 in the blood of the pulmonary capillaries. Here the cells of the 

 lung are acting against pressure, and, no matter what the inter- 

 mediate steps may be, volume energy is increased in the process, 

 and must be obtained from the chemical energy of the cell, the 

 cell protoplasm acting as the energy machine or transformer. 



Similar instances of gaseous secretion are seen (with the difference 

 in these instances that the gas is retained in solution, and the 

 increased pressure is osmotic) in the case of the secretion of saliva 

 and of bile, where in both cases the pressure of dissolved carbon 



