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CIRCULATORY SYSTEM 

 SPECIAL FUNCTIONS OF BLOOD 



BLOOD GIVES 



BLOOD TAKES 



Skin . . 



Lungs . . 

 Kidneys . 

 Small 



intestine 

 Liver . 



Water, organic salts, urea, excess 

 heat 



Carbon dioxide, water 



Water, urea 



Materials for making digestive 

 juices 



Excess protein, excess sugar, 

 secretin, worn-out red cor- 

 puscles, materials for manu- 

 facture of bile 



Oxygen 



Secretin, digested nutri- 

 ents, water 



Needed sugar, urea, excess 

 sugar, and organic sub- 

 stances 



Blood functions. As the blood circulates through the various 

 organs of the body, it gives up certain materials and takes in others. 

 Those functions that take place in all cells are called general func- 

 tions; those peculiar to any organ are called specific functions. 

 Assimilation and oxidation are activities performed in all cells; 

 therefore, they all need food and oxygen and all give up carbon 

 dioxide, water, and urea to the blood. These are known as 

 general functions. Since each organ has a special work, there are 

 certain activities performed by the blood in relation to these 

 particular functions. In the above table a list is shown of special 

 work carried on by the blood in some of the organs. 



QUESTIONS AND SUGGESTIONS 



1. Compare arteries, veins, and capillaries as to (a) position, (b) size, 

 (c) structure, and (d) function. 



2. Explain how to take a pulse. 



3. Trace a complete circulation, naming, in order, all the blood ves- 

 sels traversed from the time the blood leaves the left ventricle until it 

 returns. 



4. What is the function of each of the systems of circulation : (a) sys- 

 temic, (b) pulmonary, and (c) portal. 



