256 



Hoiv a Co?nplex Aii'wial Uses Food unit iv 



carry the others away. So every cell is 

 kept alive. 



Some organs do special jobs. In the 

 intestine blood takes on foods besides the 

 wastes. In kidneys, lungs, and skin, blood 

 loses water. You can most readily review 

 the activities of some of the important 

 organs of the body by examining the 

 following table. The first line of the 

 table shows what goes on /';/ every organ 

 all the time. The part below shows what 

 goes on over and above all this in certain 

 organs. 



The blood, as you see, not only pro- 

 vides for the continued life of each indi- 

 vidual cell (first part of table), but by 

 reaching every organ, it connects all 

 parts of the body. Because of the blood. 



an organism acts as a single unit rather 

 than as a collection of organs. But there 

 is further provision for making the parts 

 of the body work together, for making 

 the cell activities go on at a proper rate 

 and in a balanced way. This is done by 

 the hormones, the secretions of ductless 

 glands. The hormones under normal con- 

 ditions do much to regulate the proc- 

 esses of growth and development and 

 help to keep this complex body working 

 efficiently. 



While the hormones help in the regu- 

 lating of body processes, you will learn 

 in the next unit that the nervous system 

 plays an extremely important part m 

 this regulation. Our bodies are, indeed, 

 complex machines! 



x\cTiviTiEs OF Some of the Important Organs 



ORGAN 



OKCiAN RECEIVES FROM BLOOD 



ORGAN SUPPLIES TO BLOOD 



Every organ in the 

 body 



All soluble food substances 



Wastes formed in oxidation 

 (CO,, H^O, urea, uric acid. 



Liver 



Sugar (made into glycogen); 

 worn-out red corpuscles; ex- 

 cess amino acids 



At times, sugar from glycogen; 

 urea from breaking down of 

 excess amino acids 



