Contents 



Preface v 



1. Relationships of the Living World 1 



Part I. THE FOUNDATION 



2. Life Is a Concern of Matter and Energy 9 



3. Living Matter and Cells 25 



Part II. ECOLOGY 



4. Plants Provide for Themselves and Animals 51 



5. Animals and Their Environments 67 



6. Mutual Relationships of Animals 91 



Part III. THE INTERNAL ENVIRONMENT 



OF THE BODY 



7. Tissues 107 



8. An Agent in Evolution — The Body Covering 126 



9. Protection, Support, and Movement — Skeletons 135 



10. Movement — Muscles 155 



1 1 . Foods and Nutrition 168 



12. Circulation and Transportation — Body Fluids 195 



13. The Release of Energy — Respiration 224 



14. The By-Products of Metabolism — Excretion . , 242 



15. Chemical Regulation — Endocrine Glands 255 



16. Conduction and Coordination — Nervous System 279 



17. Responsiveness — The Sense Organs 309 



18. Reproduction 331 



Part IV. THE NEW INDIVIDUAL 



19. Development 359 



20. The Physical Basis of Heredity 388 



vii 



71142 



