FOODS AND WHERE THEY COME FROM 



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is used and, therefore, they can exist for longer periods 

 without food than if they were living an active life. 



We know that 

 foods spoil, but we 

 may not always 

 know the reasons for 

 this. We shall learn 

 later that there 

 are tiny plants 

 called bacteria and 

 fungi, which are 

 the cause of this 

 spoiling. They are 

 always present in 

 the air and will 

 grow rapidly when- 

 ever the conditions 

 of moisture, tem- 

 perature, and food 

 are favorable. 



How are the human body and an engine alike? 



Would these boys need the same amount of food 



if they were studying ? 



PROBLEM I. WHAT ARE FOODS AND WHERE 

 DO THEY COME FROM? 



Where Do Foods Come From? Make a list of all the 

 different kinds of food you have eaten in one day, including 

 water, salt, pepper, etc. List the foods which come from 

 animals or plants, and those that do not come from living 

 things. 



If we study this list we notice several things. First, 

 that many more foods come from plants than from 

 animals. Second, that we have a greater variety of plant 

 than of animal food and that we use more parts of plants 

 than of animals. In animals, the part we call meat is 

 really the muscle of the animal. The fat we use sparingly. 



