Contents 



Preface 



Acknowledgements 



I Keratin and Molecular Biology 



Macromolecules and biology 



Orders of magnitude 

 Types of fibrous proteins and their classification 

 Birefringence 

 X-ray methods 



The a, j8 and collagen patterns 



Stabilization 



Ecdysis 

 Distribution of the fundamental fibre-types 



Some difficulties in defining a keratin 



The significance of the variable amino acid composition 

 The fine structure of cells 



Electron microscopy and cytology 

 The cell surface, its specializations and intercellular adhesion 

 The cell membrane 



Cilia, flagella, etc 



Surface invaginations 



Specializations of opposed surfaces. Cell contacts 

 Desmosomes 



Interdigitation of confronted membranes 

 The differentiation of surface organelles 

 Cytoplasmic structures 

 Particulates 

 Membrane systems 

 The nucleus 

 Differentia 

 The phylogeny of keratinization 

 II The Keratinized Tissues 



Generalized histology of the vertebrate epidermis 

 Dermis and epidermis 

 The epidermis . . 

 The epidecmal family of cells 



H^H^mUy 



XI 



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