CHAPTER VI 



PLANT GROWTH AND NUTRITION. CAUSES OF 



GROWTH 



Problems : What causes a young plant to grow f 

 What is the relation of the young plant to its food supply ? 

 What are the outside conditions necessary for germination f 

 What does the young plant do with its food supply f 

 How is a plant or animal able to use its food supply f 

 How does a plant or animal prepare food to use in various parts 

 of the body? 



Laboratory Suggestions 



Laboratory/ exercise. Examination of a bean in the pod. Examination and 

 identification of parts of a bean seed. 



Laboratory demonstration. Tests for the nutrients : starch, fats or oils, 

 protein. Proof that such nutrients exist in beans. 



Home work. Test of various common foods for nutrients. Tabulate re- 

 sults. 



Home work. Char (partly burn) various kinds of common foods to find 

 if carbon is present. 



Extra home work hy selected pupils. Factors necessary for germination of 

 beans. Demonstration of experiments to class. 



Demonstration. Proof that materials are oxidized within the human body. 



Demonstration. Oxidation takes place in growing seeds. Test for oxida- 

 tion products. Oxygen necessary for germination. 



Laboratory exercise. Examination of corn on the cob, the corn grain, lon- 

 gitudinal sections of a corn grain stained with iodine to show that the embryo 

 is distinct from the food supply. 



Demonstration. Test for grape sugar. 



Demonstration. Grape sugar present in growing corn grain. 



Demonstration. The action of diastase on starch. Conditions necessary 

 for action of diastase. 



How Seeds are formed. — We have seen that the pollination of 

 flowers results in the growth of the fruit containing the seeds of a 

 plant. A bean pod is an example of one kind of fruit technically 

 known as a leg'ume. Each seed in the pod contains a young plant 

 or em^bryo. 



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