CONTENTS 



PREFACE 



9 



I Living Cells and What They Are Made Of 15 



II How the Cell Lives 22 



III Vitamins and Antivitamins 28 



IV Cell Division 38 

 V Inside the Cell 46 



VI Genes and Mutations 54 

 VII Effects of X-rays and Atomic Radiations on 



Living Cells 58 



VIII Viruses — Cell Parasites 67 



IX A Community of Cells 75 



X Chemical Messengers 80 



XI Antibodies and Immunity 86 



XII Cancer 93 



XIII The Origin of Life and Photosynthesis 101 



XIV Specialized Cells: Muscles, Nerves and Sense 



Organs 110 



XV The Brain and What It Does 121 



XVI Actions and How They Are Performed 131 



XVII Using Tools and Symbols 137 



XVIII Is the Brain a Calculating Machine? 143 



XIX Ageing and Death 150 



XX Life in the Universe 156 



APPENDIX I— Chemical Formulae 163 



APPENDIX II — Selected References and Books for further 



Reading . 167 



INDEX 171 



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