ELEMENTARY PHYSIOLOGY. 
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tissue metabolism. These waste materials are partly got rid of by 
a portion of the blood being sent through the liver and kidneys. 
The blood returns to the right side of the heart (the right auricle), 
and from here it is pumped by the right ventricle through the lungs, 
where it gets rid of the carbonic acid gas and other effete material 
received from the tissues and takes up a fresh supply of oxygen. 
From the lungs it returns to the left side of the heart (left auricle) 
to be again pumped through the body by the left ventricle. 
