6 HITCHCOCK'S ANATOMY 



describes the different organs of animals. Physiology describes 

 their functions, or uses. If the organs of man alone be de- 

 scribed, the science is called Human Anatomy and Physiology. 

 If the description embrace the lower animals, it is called Com- 

 parative Anatomy and Physiology. 



7. Another definition of Anatomy, is the science of Organ- 

 ization ; and of Physiology, the science of Life. 



8. Animal and Vegetable Anatomy and Physiology. — 

 There are also such sciences as Vegetable Anatomy and 

 Physiology. Indeed, there is a strong analogy between the 

 organs of plants and animals, and their uses. Nor is it easy 

 always to draw the line between plants and animals, where 

 they approach the nearest to each other. 



9. Intimate Connection of Anatomy and Physiology. — 

 Few writers confine themselves to the structure of animals, 

 when treating of their anatomy, but treat also of the function 

 of their organs ; and the same thing is still more generally 

 true of writers on physiology. We do not separate these 

 sciences in this treatise. 



10. Fifteen Chemical Elements in the IIumanBody. — Of 



the sixty-five chemical elements or simple bodies known to 

 exist, only fifteen have been found as normal constituents of 

 the human body. The following is the list : — 



1. Oxygen, 



2. Hydrogen, 



3. Carbon, 



4. Nitrogen, 



5. Sulphur, 



6. Phosphorus, 



7. Calcium, 



8. Magnesium, 



9. Sodium, 

 10. Potassium, 



11. Chlorine, 



12. Fluorine, 



13. Silicon, 



14. Iron, 



15. Manganese. 



11. Carbon, Hydrogen, Oxygen, and Nitrogen.— The first 

 three of the above elements are found in all the solids and fluids 

 of the body, without exception. The first four occur in all the 



What is Physiology ? When is the term comparative applied? 7. Give a more con- 

 cise definition of Anatomy and Physiology. 8. Describe animal and vegetable Phy- 

 siology. 9. Speak of the close relationship between Anatomy and Physiology. State 

 the whole number of chemical Elements. 10. State those which are found in the human 

 body. 11. Where are the first three found? Nitrogen also? 



