SUMMARY OF PART II 421 



SUMMARY OF PART II 



For the maintenance of life the needs of the cells must 

 be supplied and the body as a whole must be brought into 

 proper relations with its surroundings. The last-named 

 condition requires that the body be moved from place to 

 place ; that its parts be controlled and coordinated ; and 

 that it be adjusted in its various activities to external phys- 

 ical conditions. To accomplish these results there are 

 employed : 



1. The skeleton, or bony framework, which preserves 

 the form of the body and supplies a number of mechani- 

 cal devices, or machines, for causing a variety of special 

 movements. 



2. The muscular system, which supplies the energy 

 necessary for executing the movements of the body. 



3. The nervous system, which (a) controls and coordi- 

 nates the various activities and (#) provides for the intelli- 

 gent adjustment of the body to its environment. (Review 

 Summary of Part I, page 215, and consult Fig. 92, page 

 214.) 



