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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). 



Blood-corpuscles. 



Blood-plasma. 



Cl 1.75 



K 2 O 3.091 



Na 2 O .0.470 



S0 3 0.061 



P 2 O 5 1.355 



CaO . . . . 



MgO 



Cl 3.536 



K 2 O 0.314 



Na 2 O 3.410 



SO 3 0.129 



P 2 6 5 0.145 



CaO 



MgO 



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 : 



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. 



