16 GENERAL BIOCHEMISTRY 



tions with organic compounds. For example, certain coenzyme systems, 

 essential for normal metabolism, contain phosphates as part of the 

 coenzyme molecule. Certain essential amino acids contain sulfur in 

 highly reactive form. These and other inorganic elements will be dis- 

 cussed in subsequent chapters. 



Proteins, lipides, and carbohydrates contain carbon, combined in 

 various combinations with other elements, of which hydrogen, oxygen, 

 nitrogen, and sulfur are most important. These compounds play a 

 major role in normal plant and animal growth. In subsequent chap- 

 ters we shall consider the chemical structure and properties of carbo- 

 hydrates, lipides, and proteins in considerable detail. 



REFERENCE 



A Source Book of Agricultural CJiemistry. C. A. Browne. G. E. Stechert and Co., 

 New York. 1944. 



