392 



THE RESPIRATION 



them into the plasma of acid radicles. At least it has been found that 

 the alkalinity of the plasma increases when C0 2 is bubbled through 

 blood, this increase in alkalinity being interpreted as the result of the 

 migration of acid radicles into the corpuscles. This would lead us to 

 expect that under the opposite conditions (i. e., in vacuo) acids would 

 leave the corpuscles. 



Proteins are amphoteric substances that is, they combine with acids 

 or alkalies which would lead us to expect that they would be capable 

 of absorbing some C0 2 . That this is the case, particularly for hemo- 



75 



70 



65 



60 



50 



40 



A 



30 40 



60 70 

 vn. rtvm. 



80 



90 



Fig. 142. Curve of CO 2 tension in blood. For description, see text. (From Christiansen, ' Doug- 

 las and Haldane.) 



globin, has been shown by comparing the C0 2 -combining powers of water 

 and a solution of pure hemoglobin. 



Attempts have been made to determine the relative amounts of C0 2 

 carried by these various agencies in the blood. The following is an ex- 

 ample of such a table: 



In simple solution in plasma and corpuscles 



] a in corpuscles 6 



As sodium bicarbonate } ^ in plagma 12 



In combination with hemoglobin 7.5 



In combination with proteins of plasma 11 



1.9 c.c. 

 8 " 



8 1 

 .0 } 18 ' 



"I } 19.3 " 

 .8 J 



(Loewy.) 



40.0 



