Biology of Man 527 



not pass. Careful and scientific study of the results of legalized and con- 

 trolled sterilization in various states has indicated favorable progress. 

 Wars of the past which have claimed many of our best youths have robbed 

 us of countless good prospective parents of future offspring. It is also 

 known that the number of children produced by parents possessing in- 

 ferior traits is far greater than the number produced by superior parents. 

 In a short time the entire race will be affected by this rapid increase in 

 the less desirable traits. Every possible measure should be taken to in- 

 crease the birth rate among the better endowed families rather than let 

 it continue to decrease as at present. Every possible measure should be 

 taken to reduce as far as possible the birth rate of undesirable parents. 

 More of the better types of offspring, fewer of the poorer types, together 

 with the best of environments (educational, religious, home, recreational, 

 occupational, etc.) in which the inherited materials can develop, will 

 improve mankind. 



QUESTIONS AND TOPICS 



1. List the systems of the human body with the important general functions of 

 each. 



2. Explain the phenomenon of cellular differentiation and its effects in the hu- 

 man body. 



3. Explain why the human skin is sometimes spoken of as "the jack of all 

 trades." Describe the anatomy of the skin layers and the functions of each. 



4. Explain the origin of (1) teeth, (2) nails, (3) sebaceous glands, and (4) 

 hair. 



5. Explain why there are more men afflicted with inheritable baldness than 

 women. 



6. Describe the process of heat production, distribution, equalization, and elimi- 

 nation in the human body. 



7. Contrast human and frog skins, giving differences in structure and functions. 



8. Describe each of the embryologic origins of bones, with an example of each. 



9. Compare and contrast the three types of muscle tissues in as many ways as 

 possible from a structural and functional standpoint. 



10. List several methods used in naming skeletal muscles. 



11. Define the following terms as applied to muscles: origin, insertion, voluntary, 

 involuntary, abductor, adductor, striated, and nonstriated (smooth). 



12. Explain in detail the physiologic process of digestion of various foods in man. 



13. Explain why all substances in nature are not desirable for human foods. 



14. Explain specifically why we cannot inhale air and swallow food at the same 

 time. 



15. List the properties, common sources, and effects produced by each of the more 

 common vitamins. 



16. List the chemical formula for each vitamin, commenting on the similarity or 

 dissimilarity of the various formulae. What does this mean ? 



