The biochemical hierarchy

This is a diffnse and loosely dehned system which encompasses those cells and tissnes that are phagocytic. These include the endothelia of blood and lymphatic vessels (which are only weakly phagocytic), reticnlar cells of the spleen, endothelial cells, sinnsoids in the liver and lymph nodes, macrophages and drcnlating phagocytes. 

in fact, possible to separate disease into classes that loosely correlate with the different systems in the human body, which are described above. These classes are listed in Appendix 1.1 together with an indication of the positions in the book where the diseases are described and discussed. 

Two examples are provided here and expanded further in later chapters. 

Mitochondria One characteristic of human life is movement and physical activity. It is the mitochondria in muscle that generate ATP to support the process of contraction of the myofilaments in the muscle fibre which results in contraction of the whole muscle. 

Failure of mitochondria to generate sufficient ATP to power contraction of the muscles leads to fatigue, which 

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