io6 BIOLOGY AXD HUMAN LIFE 



3. Regulators (influencing growth and other processes) 



Vitamins 



Fat-soluble A ; water-soluble B ; water-soluble C 

 B. Inorganic needs of protoplasm 



4. Water 



Solvent Medium in which proteins etc. 



Transportation agency are suspended 



5. Oxygen 



Combining with organic matter and so yielding energy 



6. Salts 



Activators Building material in part 



Regulators (lime in bones) 



QUESTIONS 



1. What distinction should you make between feeding and eating? 



2. What income of the body does not come through the mouth ? 



3. What kinds of nutrients would be used in relatively large quantities 

 by a person who is growing rapidly ? 



4. What kinds of nutrients would be used in relatively large quantities 

 by a person who is very active ? 



5. Why do we drink more w^ater in warm weather than in cold ? 



6. W'hat are some of the more important sources of proteins ? of fats ? 

 of carbohydrates ? 



7. What are some of the more important sources of fat-soluble vita- 

 min A ? of water-soluble B ? of water-soluble C ? 



8. What are some of the more important sources of salts in our diet ? 



REFERENCE READINGS 



Hough and Sedgwick. The Human Mechanism, pp. 91-99. 



OsTERHOUT, W. J. V. Experiments with Plants, pp. 164-178. 



Farmers' Bulletin 800, Foods the Body Needs. 



Harrow, Benjamin. Vitamines, Essential Food Factors, chap, ix, Vita- 

 mines (extract in C. H. Ward's ''Exploring Nature," pp. 186-189). 



United States Department of Agriculture. Bulletin 1138, Vitamin B in 

 Edible Tissues of Ox. Sheep, and Hog. 



Public Health Reprint 689, Antineuritic Vitamin in Skim-Milk Powder. 



