V. PLANT GROWTH AND NUTRITION. CAUSES OF 



GROWTH 



Problem. — What causes a young jjlant to grow ? 

 (a). The relation of the young plant to its food supply, 

 ih) The outside conditions ivecessary for germination. 



(c) What the young plant does with its food supply. 



(d) How a plant or animal is able to use its food supply. 



(e) How a plant or aniinal prepare food to use in various 

 parts of the body. 



Laboratory Suggestions 



Laboratory exercise. — Examination of bean in pod. Examination and 

 identification of parts of bean seed. 



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

 oils, protein. 



Laboratory demonstration. — Proof that such foods exist in bean. 



Home work. — Test of various common foods for nutrients. Tabulate 

 results. 



Extra home work by selected pupils. — Factors necessary for germina- 

 tion of bean. Demonstration of experiments to class. 



Demonstration. — Oxidation of candle in closed jar. Test with lime 

 water for products of oxidation. 



Demonstration. — Proof that materials are oxidized within the human 

 body. 



Demonstration. — Oxidation takes place in growing seeds. Test for 

 oxidation products. Oxygen necessary for germination. 



Laboratory exercise. — Examination of corn on cob, the corn grain, 

 longitudinal sections of corn grain stained with iodine to show that embryo 

 is distinct from food supply. 



Demonstration. — Test for grape sugar. 



Demonstration. — Grape sugar present in growing corn grain. 



Demonstration. — The action of diastase on starch. Conditions neces- 

 sary for action of diastase. 



What makes a Seed Grow. — The general problem of the pages 

 that follow will be to explain how the baby plant, or embryo, 



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