CHAPTER I. INTRODUCTORY 



Plants and animals, 1 ; intermediate organisms, 3 ; vitality, 

 3 ; definition of Biology, 4 ; morphology and physiology, 4 ; 

 limits of the present volume, 5. 



CHAPTER II. THE FUNCTIONS OF THE ORGANISM 

 Nutrition, 6 ; sensitivity, 7 ; reproduction, 8. Illustrative 

 examples, 8 ; Vaucheria, 9 ; frog, 13. Summary, 16. 



CHAPTER III. DIFFERENTIATION OF STRUCTURE AND DIVISION 



OF LABOUR 



Cells, 18 ; unicellular organisms, 18 ; Amoeba, 19 ; leucocyte, 

 19 ; Pleurococcus, 19. Nutrition and locomotion, 20. Multi- 

 cellular organisms, 20 ; Hydra, 21 ; Enteromorpha, 23. Differen- 

 tiated multicellular organisms, 23 ; tissues, 23. Division of 

 labour and specialisation of structure, 24 ; comparison of a 

 differentiated multicellular organism and a human society, 24 ; 

 progressive differentiation in individuals during development 

 from the germ, 25. 



CHAPTER IV. FOOD AS A SOURCE OF ENERGY 

 Chemical analysis of an organism, 27 ; source of the chemical 

 elements, 27 ; nature of food, 27 ; average daily diet of a human 

 individual, 28 ; work and energy, 28 ; conservation of energy, 

 29 ; measurement of energy, 29. Food as a store of potential 

 energy, 31 ; oxidation and release of energy, 31 ; deficiency of 

 oxygen in organic compounds, 32 ; respiration, 33 ; other 

 methods of releasing energy, 34. 



CHAPTER V. THE TRANSFORMATION OF FOOD 

 Digestion, 35 ; in animals, 35 ; enzymes, 36 ; alimentary tract 

 and associated glands, 37 ; in plants, 39 ; carnivorous plants, 40. 



CHAPTER VI. THE MANUFACTURE OF ORGANIC FOOD 

 The chlorophyll apparatus, 42 ; absorption from the soil, 44 ; 

 root- hairs, 44 ; law of osmosis, 45 ; transpiration, 46 ; stomata, 

 46 ; nature of solar energy, 47 ; absorption spectrum of chloro- 

 phyll, 47 ; photosynthesis, 48 ; chemosynthesis, 48. Summary, 

 48. Parasites, 49 ; saprophytes and saprozoa, 49 ; symbionts, 

 49 ; carnivorous plants, 50. Circulation of materials, 50. 



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