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AN AMERICAN TEXT-BOOK OF PHYSIOLOGY. 



removing the waste products of their functional activity. The constituents 

 existing in quantities sufficiently large for recognition by chemical means are 

 as follows: (1) Water; (2) proteids, of which three varieties at least are 

 known to exist in the plasma namely, fibrinogen, paraglobulin (serum- 

 globulin), and serum-albumin; (3) combined proteids (haemoglobin, nucleo- 

 albumins) ; (4) extractives, including such substances as fats, sugar, urea, 

 lecithin, cholesterin, etc. ; and (5) inorganic salts. The proportions of these 

 substances found in the blood of various mammals differ somewhat, although 

 the qualitative composition is practically the same in all. 



The following tables, taken from different sources, summarize the main 

 results of the quantitative analyses which have thus far been made : 



Analysis of the Whole Blood, Human ( C. Schmidt). 



Inorganic Salts of Human Blood, 1000 parts (C. Schmidt). 



These acids and bases exist, of course, in the plasma and the corpuscles as 

 salts. It is not possible to determine exactly how they are combined as salts, 

 but Schmidt suggests the following probable combinations : 



Probable Salts in the Corpuscles. 



Probable Salts in the Plasma. 



Potassium sulphate 0.132 



Potassium chloride 3.679 



Potassium phosphate 2.343 



Sodium phosphate 0.633 



Sodium carbonate 0.341 



Calcium phosphate 0.094 



Magnesium phosphate .... 0.060 



Potassium sulphate 0.281 



Potassium chloride 0.359 



Sodium chloride 5.546 



Sodium phosphate 0.271 



Sodium carbonate 1.532 



Calcium phosphate 0.298 



Magnesium phosphate .... 0.218 



One interesting fact brought out in the above table is the peculiarity in 

 distribution of the potassium and sodium salts between the plasma and the 

 corpuscles. The plasma contains an excess of the total sodium salts, and the 

 corpuscles contain an excess of the potassium salts. 



