ORGANS APPARATUS- FUNCTIONS. 23 



20. The different phenomena by which life manifests itself, arc 

 always the result of the action of some part of the living body ; 

 and these parts, which may be regarded as so many instruments, 

 are called ORGANS. 



21. Thus, an animal cannot move without the action of certain 

 organs called muscles, or attain a knowledge of that which sur- 



ounds him except by the intervention of the organs of sense. 



22. When several organs concur to produce the same phenome 

 non, the assemblage of instruments is termed an APPARATUS. 



23. We say, for example, tlie apparatus of locomotion to desig- 

 nate the assemblage of organs which serve to transfer an animal 

 from one place to another ; and, apparatus of digestion to desig- 

 nate the assemblage of organs, by the assistance of which the 

 animal digests its food. 



24. The action of one of these organs, or of one of these 

 apparatus or the use for which they are designed, is called a 

 junction. 



25. We say, therefore, function of locomotion, to designate the 

 action of all the parts of the apparatus of locomotion ; the function 

 of digestion, to designate the action of the different parts which 

 constitute the digestive apparatus; and functions of the stomach, 

 functions' of the intestines, functions of the teeth, $~c., to designate 

 the vses of these different organs. With man, as well as with 

 all quadcupeds, birds and a majority of other animals, the 

 organs, and the functions which the latter exercise, are very 

 various. 



26. Considered individually, the body of the majority of animals 

 is divided into three principal portions ; the htad, the trunk, and 

 the members, or extremities. 



27. The head, which is not found with all animals, oysters for 

 instance, is subdivided into two parts ; the cranium or skull and 

 the face. 



28. The trunk is composed also of two parts; the ch*+* or 

 thorax, and the belly Or abdomen. 



20. What is meant by an organ? 



21. Give an example of an organ? 



22. What is an apparatus ? 



23. What are the examples of an apparatus ? 



24. What is a function ? 



25. Give examples of what is meant by the term function. 



26. How are the bodies of animals divided ? 



27. Does every animal possess a head ? What are the divisions of the 



MA 9 



Of how many parts is the trunk composed ? What are they 7 

 D 



28. 



