70 PLANT GROWTH AND NUTRITION 



solution of grape sugar and water. Collect in a beaker the filtrates 

 (the substances that pass through the filter paper). 



Observations. — Do the contents of both funnels pass through 

 the filter papers? Test the contents of the vessels into which 

 the contents of the first and second filter have passed, the first 

 with iodine, the second with Fehling's solution. What happens? 



Conclusion. — 1. If the corn seedling absorbs or takes in food, 

 what forms must it be in? How do you know? 



2. What is the purpose of digestion in plants? 



Problem Questions 



1. What results from the fertilization of a flower? 



2. What are the uses of the various parts of a plant embryo ? 



3. How is an embryo protected? (Think of a corn or bean 

 embryo.) 



4. What are nutrients ? 



5. How could you detect starch, protein, grape sugar, or oil in 

 any substance? 



6. Why would it be necessary to mash up or boil a substance 

 which you wished to test for starch? 



7. How could you detect the presence of mineral matter in a 

 bean? 



8. How could you test for the presence of water in a substance? 



9. Name five substances containing starch; fat; protein. 



10. What conditions are necessary to make an embryo grow? 



11. Why is air necessary? Explain just what air does. 



12. Could a plant do work without oxygen? Explain. 



13. What happens as a result of oxidation of wood or coal? 



14. What happens when oxidation takes place in the body? 



15. How could you prove that plants and animals use oxygen 

 for the same purpose? 



16. What is an ear of corn? A grain of corn? Explain with 

 reference to diagrams in your Civic Biology, pages 67, 69. 



17. How and where is food stored in a corn grain? 



18. A corn grain grows. How can it get its food so as to make 

 use of it? 



