778 General and Applied Biology 



leum. Paper is made from straw, bark, wood, and other fibrous plant 

 materials. Coke is manufactured from certain kinds of coal by heating 

 in the absence of oxygen. For a more complete consideration of this 

 phase of resources, see chapter on the Economic Importance of Plants. 



III. BIOLOGY AND ITS RELATION TO 

 HUMAN WELFARE 



A. Medicine and Health 



In few fields have the contributions of biology been greater than in 

 medicine and health. Courses in biology have given training for large 

 numbers of premedical students who have had the qualifications later 

 to enter the medical profession. Through animal experimentation, many 

 of the fundamental and basic truths of behavior, health, diseases, and 

 similar phenomena have been ascertained, with their subsequent appli- 

 cation in the field of medicine and public health. An experimental study 

 of animal reactions and behavior has suggested methods to be employed 

 in attacking the problem of individual and group behavior in man. 



Many of the medicines used today are of plant or animal origin. In 

 addition, the efficiency and proper use of medicines have been deter- 

 mined largely through animal experimentation. Much of our knowledge 

 of foods, their correct use, their composition, their preservation, their 

 transportation, as well as diseases which they cause or transmit, are all 

 dependent upon certain biologic facts. The parasites of plants, animals, 

 and man have been studied in detail, and the information acquired has 

 been used successfully in making our environment a better place in which 

 to live. Many of the life cycles of parasites have been carefully studied 

 and this knowledge applied to the elimination of many of them. Re- 

 search in the fields of bacteriology and protozoology has contributed 

 many facts which, when practically applied, have resulted in lower 

 morbidity and mortality rates among living organisms. Heredity has 

 made a great contribution in explaining how we have come to be what 

 we are, how certain abnormalities arise, and how we may eliminate some 

 of the undesirable traits by the proper application of the knowledge 

 gained through the study of heredity. 



Many of the improvements in our environment have been suggested 

 and influenced by what we have learned by biologic investigations. The 

 proper treatment of sewage, the purification of water, the inspection and 

 refrigeration of foods, the rigid inspection of oysters and other shell foods 

 for possible contaminations are only a few of the contributions in this 



