58 HUMAN BIOLOGY 



1. Name the foods represented in Figure 22 that are derived 



from animals ; name those obtained from plants. 



2. On the average, can larger amounts of the animal or of 



the vegetable foods represented on the chart be pur- 

 chased for 25 cents ? 



3. Bearing in mind the relative work and expense in pro- 



ducing animal and vegetable foods suggest some 

 explanations for the answer you have given to ques- 

 tion 2. 



4. Which one of the foods on the chart would you buy if 



you wished to get the largest amount of solid nutri- 

 tion for 25 cents; that is, which food is the most 

 economical ? 



5. From which kind of food would you get the smallest 



amount of solid nutrients? Name other foods on 

 the chart which are more expensive per pound than 

 the one that you have just named. 



6. Which of the three kinds of beef named on the chart 



would be the most economical for soup or stew? 



7. Name three classes of food substances needed in the diet 



of the average American engaged in moderate work 

 (see last line on the chart), and estimate the weight 

 of each that is needed during a day. 



8. Which food on the chart comes the nearest to supplying 



in the right proportions all the nutrients named in 7 ? 

 In the food you have named which kind of food sub- 

 stance is not present in sufficient proportion ? 



9. Why is it better to eat a variety of foods rather than 



any one kind? 



10. Suggest a reason why meat and potato should be eaten 

 together ; bread and butter. 



70. Economy in the purchase of foods. The animal 

 foods, we have just learned, are considerably more expensive 

 than the staple foods of vegetable origin. Hence, in an 

 economical household the proteins needed by the body 

 should be largely obtained from vegetable foods like bread, 

 corn meal, and beans. If this plan were followed, a con- 



