4 KERATIN AND KERATINIZATION 



molecular elements most easily studied by electron microscopy or X-ray 

 diffraction. 



A brief description of these and other specialized techniques will be 

 given in the course of the text when it is necessary to make the discussion 

 clear, but for an adequate account of the methods reference must be made 



Fig. 1. Levels of organization of biological structure and range of 

 instruments. 



