DEFENSIVE FERMENTS OF THE ANIMAL ORGANISM 



this way a cell dies, though it be plentifully sur- 

 rounded by a material rich in energy, which, how- 

 ever, cannot be used because it lacks the proper form 

 -both structural and configurative. It does not suit 

 the organization of the cell. There is an abundance 

 of oxygen at its disposal, but the latter cannot find 

 any point of attack ; and so the necessary preparation 

 is wanting. 



Some of the substances cannot be absorbed bv the 



j 



cell, simply because they are physically too coarse to 

 penetrate through the cell wall. Such is the case 

 with many colloidal substances, which must be first 

 decomposed into simpler groups before they can 

 pass into the interior of the cell. In these cases the 

 presence of ferments is essential, and they have TO 

 be of such a kind as to be capable of decomposing 

 the complicated molecules into a form which may 

 easily penetrate through the cell wall. Often, how- 

 ever, such conditions may suffice as enable the 

 coarse complex substance to be simply broken up into 

 finer particles, which may be ingested in this form by 

 the cell, without any molecular decomposition being 

 necessary. Further decomposition takes place during 

 absorption or, even later, at a suitable point within 

 the cell. 



Even a unicellular organism does not enter into 

 intimate relations with substances which have 

 not previously been remodelled. This remodelling 



