PROTOrLAS.MIC STRUCTURE 83 



i.e., material concentrated or condensed at the proto- 

 plasmic surfaces may in this manner first become capable 

 of chemical interaction. In a recent pa])er' Hayliss 

 gives instances showing that in many reactions in poly- 

 phasic systems adsorption is the initial process which 

 forms a necessary' preliminary to the true chemical com- 

 bination following. 



We may conclude that the determination and control 

 of chemical reactions by adsorption are universal in 

 living protoplasm. The presence of colloidal comj)lexes 

 or ''adsorption compounds" — e.g., compounds of lecithin 

 with proteins, such as lecithin-vitellin (in the ethereal 

 extract of egg yolk) and jecorin (dextrose and lecithin 

 plus protein) — is frequent in organisms. Inorganic 

 salts and ions are probably also largely present in a con- 

 dition of adsorption;^ and the indications are that the 

 action of the surface-active pharmacological compounds 

 (especially the anaesthetics) is largely so determined. 

 According to Loewe, the chief relation between lipoids 

 and narcotic compounds is one of adsorption,*' although 

 the relative solubilities of these compounds in the 

 different protoplasmic phases (partition-coefficients) 

 probably also enter as an important factor in narcotic 

 action.'' 



The promotion of chemical action by adsoq)tion 

 is often called ''adsorption-catalysis." Well-known 

 examples are the formation of U^SO^ from SO, in the 

 presence of platinum, the reduction of various compounds 



^ Proceedings of the Royal Society, B, LXXXIV (1911), 81. 

 ' Cf . Pauli, loc. cit. 



3 Loewe, Biochem. Z., LVII (1913), 161; cf. pp. 2cx) IT. 



4 See chap, ix for the relation of adsorption to narcosis. 



