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THE MINERAL CONSTITUENTS OF BLOOD. 



Comparison of To the mineral substances in the cells and plasma of the 

 constituents of Wood respectively, attention should be particularly directed, 

 the cells and smce they indicate the functions of these portions. 



plasma. 



Mineral Constituents in 1000 Parts of the Blood. 



The amount of inorganic matter in the cells and plasma, respectively, 

 of 1000 parts of blood being nearly the same, the table shows that there 

 is more than twice as much chlorine, and more than three times as much 

 sodium in the plasma as in the cells. It may thence be inferred that the 

 chloride of sodium is, for the most part, in the plasma. Moreover, there 

 is six times as much phosphorus, and more than ten times as much po- 

 tassium, in the cells as in the plasma ; and therefore it may be inferred, 

 since potash is required to so great an extent in the nutrition of the mus- 

 cular system, and phosphorus as an element of the phosphorized oils in 

 the nervous, that the cells have a direct functional relation to those im- 

 portant mechanisms, and this in addition to their duty of introducing 

 oxygen. 



The mineral constituents of the blood discharge very different duties, 

 Functions of some, either directly or indirectly, acting functionally, others 

 consTituenfsof as histogenetic bodies. Thus the alkaline properties of the 

 the blood. blood are due to the presence of the carbonate and phosphate 

 of soda, and this latter substance enables the serum to hold in solution 

 carbonic acid, and thus it maintains a relation in the respiratory opera- 

 tion. But the phosphate of lime discharges a true histogenetic function, 

 since upon it the bony system depends for its nutrition. The mutual 

 relations of these substances are, of course, very complex, though often 

 of importance. Thus, of the two just mentioned, the phosphate of soda 

 enables the serum to hold the phosphate of lime in solution. 



The tawny coloring matter of serum diifers from cholepyrrhin in not 

 Coloring mat- yielding the characteristic reaction of that body. The tint 

 ter of serum, sometimes becomes quite deep, owing to several different 

 .causes, such as the undue accumulation of the coloring matter of urine, 

 through disturbance of renal action, or from bile pigment, as in icterus. 



The gases which can be disengaged from the blood occur in the cells, 

 according to Magnus, a statement which, however, is very far from being 



