256 FIRST YEAR COURSE IN GENERAL SCIENCE 



mals and plants possess the property of taking up such sub- 

 stances. This property of taking food and converting it into 



energy or the material of the 

 body is nutrition. 



The food of the young 

 plant is mainly starch, a 

 compound of carbon, 

 hydrogen, and oxygen; and 

 proteid, which is a compound 

 of these elements with 

 nitrogen and traces of others. 

 This food material is stored 

 in the seed and from it, to- 

 gether with water absorbed 

 from the ground, is formed 

 the material of the first root, 

 stem, and leaves of the plant. 

 Some plants grow many inches 

 in height with no food but 

 that in the seed. The newly 

 hatched fish or chicken, turtle 

 or bird, has grown to a con- 

 siderable size from the ma- 

 terial stored within the 



FIG. 135. GROWTH FROM FOOD 

 STORED IN THE SEED 



A garden pea was sprouted in 

 a damp place. It was then placed 

 so that the sprout passed through 



egg- 

 But the life processes can- 



hole in a piece of cheese-cloth not Continue Without energy, 



stretched over a tumbler of water. & more than a machine can 



Fig. 135 represents a growth of 



several days. The roots, stem, and run Without power. 



leaves have developed. 



they been made from? 



As we 

 what have j iaye geen? energ y i s derived 



from oxidation. The food 

 provides the material to be oxidized, but oxygen also is 

 necessary. The power to take oxygen, or respiration, is a 

 part of the property of nutrition. Respiration is much 

 more noticeable in animals than in plants, * 



