CHAPTER II 



THE BASIS"~OF : 7LIFE 



PROTOPLASM was defined by Huxley as " the physical basis of 

 life." It is the material substance which lives. There is no life 

 in anything which does not consist of, or is not supported 

 upon, or permeated by a system of filaments of protoplasm. 

 Huxley's definition indissolubly links in thought protoplasm 

 and life. But it is doubtful whether the definition is in any 

 sense axiomatic. The adjective " physical " has too narrow a 

 range. If the biologist could say to the chemist, " Here is a 

 substance which was alive. If I could restore to it the energy 

 which it has lost, if I could impart to it the movement which 

 I recognize as life, it would again be alive," he would offer the 

 chemist a substance susceptible to the methods of his science, 

 something which he could analyse. If, approaching the physi- 

 cist with a group of chemical products, he could say, " Into 

 these protoplasm broke up on dying. I cannot assure you that 

 while it was alive they were combined into molecules within 

 your meaning of the term. There may be no such ' sub- 

 stance ' as protoplasm in the sense in which you understand 

 the word, but so long as this mass lived these various familiar 

 compounds were bound together in a supermolecular form. 

 Death was their falling apart. If I could cause them to 

 recombine, they would be alive," he would give the physi- 

 cist a problem within the range of his methods. The physi- 

 cist could devise a method for measuring these units. The 

 science which can weigh an electron, the thousandth part of 

 an atom, need not fear failure in its attempt to gauge the 

 size of units of structure composed of groups of heavy mole- 

 cules, albumins, globulins, and other proteins,* with the inclu- 



* Protein, subs., proteiid, adj., general terms for complex nitrogenous sub- 

 stances, such as albumin (white of egg), the less soluble globulins, fibrin of 

 blood casein of milk, etc. 



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