Extension Wokk in Hoeticultcee. 187 



The Nutrition of Plants. 



(Given at first Fredonia School.) 



(Br Professor Howlee.) 



1. Nutrition is one of the two primary functions of all organ- 

 isms. The other is reproduction. 



2. There are different methods of taking food. Amoeba absorbs 

 its food through the walls of its body. In higher forms a body 

 cavity is developed and food is absorbed only through its walls. 

 The culmination of complexity of structure is reached in the highly 

 complicated respiratory and digestive systems of the higher animals. 



3. To understand the relation of nutrition in plants to nutrition 

 in animals, one mnst go back to primitive methods of taking food. 



4. There are two great operations going on in living beings, one 

 a building up process (constructive), the other a tearing down pro- 

 cess (destructive). 



5. These processes may be distinguished, — (a) by the materials 

 used as food, (b) by the structure of the operating organs, (c) by the 

 product of the operation. 



6. There is no hard and fast line separating animals from plants. 

 The method of nutrition prevailing among plants is one of the most 

 decisive characters. 



7. The chlorophyll function (photosynthesis). 



8. The content of the vegetable cell is primarily protoplasm. 

 This in active cells is differentiated in two parts, — the nucleus, at 

 the center, and the ectoplasm, the lining membrane of the wall. 

 The former displays greater activity in the process of reproduction, 

 the latter, in those of nutrition. 



9. The green pigment, chlorophyll, which gives the green color 

 to plants is fixed in minute differentiated masses of protoplasm, called 

 chlorophyll bodies. 



10. Various forms of chlorophyll bodies, — Oscillaria,— Spi- 

 rogyra, — Chara, — Coleus. 



11. Movement of the chlorophyll bodies occurs in all plants so 

 far as known. It is rapid in Elodea and Yallisneria. 



12. Conditions best suited to activity of these workers. Import- 

 ance of sunlight. Pruning to avoid waste of energy. 



13. Plants without chlorophyll. 



14. General conclusions. 



