SURVEY QUESTIONS 



How can roots take substances from the soil? Why do farmers use 

 fertilizers ? Is it true that green plants are the largest food manufactories 

 in the world. What do we mean by " corn on hoof " ? Why do we plant 

 trees in city parks ? What value might green plants be in your home ? 



Photo by Wright Pierce 



UNIT VI 



GREEN PLANTS AS FOOD MAKERS AND FOOD 



USERS 



Preview. All of you will agree with the statement that food is 

 probably the most important material in the world. There would 

 be little chance for life on the earth if our food supply was taken 

 away and we had no way of getting a new one. This is exactly 

 what would happen if green plants would disappear from the 

 earth. If you think it out, you can easily prove that all animals 

 are dependent on green plants for food. For example, cows eat 

 grass, and in turn, give man milk and meat. Plants may furnish 

 man with food directly as vegetables, cereals, and fruits. Even 

 the walrus and seal in the arctic regions, which at first sight would 



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