X CONTENTS 



PAGE 



Relation of Cells 32 



Ameba 36 



Paramecium 39 



Bacteria 44 



CHAPTER IV 



What Makes Man Go 



Energy from the Food Eaten 52 



Chemical Energy 53 



Oxygen and Respiration 54 



The Plant Manufactures Food 55 



Kinds of Food 58 



Chemicals in Foods 62 



Chemicals in Body of Man 63 



Man's Efficiency in Utilizing Foods 65 



CHAPTER V 

 The Law of Biogenesis 



Germ Cells and Body Cells 71 



Structure of Germ Cells 74 



Fertilization 81 



The Embryo 84 



CHAPTER VI 



Reproduction in Man 



Human Germ Cells 86 



Fertilization in Man 89 



Cause of Sex 90 



Reproduction, a Normal Process in All Men ... 91 



Necessity for Special Reproductive Organs in Man . . 92 



Puberty 94 



Sex Instruction 98 



