TABLE OF CONTENTS 



PAGE 



WHY AND HOW WE STUDY BIOLOGY . . . . . 1 



PART I 



LIVING THINGS IN RELATION TO EACH OTHER 

 AND THEIR SURROUNDINGS 



UNIT I. THE WORLD WE LIVE IN AND WHAT WE 

 TAKE FROM IT 



PROBLEM 



I. What Does a Tree Take from Its Surroundings? . . 21 

 II. What Are the Building Materials of the World and 



How Are They Used? 23 



III. What Are Foods and How Are They Used? ... 30 



IV. How Does Man Control His Environment? ... 32 



UNIT II. WHAT IS BEING ALIVE? THE FUNCTIONS 

 OF LIVING THINGS 



I. What Do We Mean by Reactions to Stimuli? ... 39 



II. How Are Living Things Alike and How Do They Differ? 43 



III. What Are Cells and How Do They Produce Others? . 46 



IV. What Do We Mean by Adaptation? 49 



UNIT III. HOW ARE PLANTS AND ANIMALS 

 MUTUALLY DEPENDENT? 



I. What Are the Inter-relationships of Plants and Animals? 57 

 II. To Know Something of the Structure and Life History 



of the Grasshopper 62 



III. To Know Something about the Structure and Life 



History of the Butterfly 65 



IV. What Do We Mean by Communal Life and Division 



of Labor? 69 



V. What Are the Characteristics of Other Groups of Insects ? 75 

 VI. Why Are Insects So Numerous? . . . . . .80 



VII. Of What Use Are Flowers to Plants? .... 83 



VIII. How Are Fruits Formed? .86 



IX. What Are Some Adaptations in Insects for Carrying 



Pollen? 88 



X. What Are Some Specific Examples of Cross Pollination? 91 



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