III. THE MANNER IN WHICH DIFFERENT 

 KINDS OF WORK ARE DIVIDED AMONG 

 THE MEMBERS OF THE BODY 



19. Kinds of ivork, or functions of the plant. — 

 In accomplishing the purpose of its existence a plant 

 is compelled to do a large number of different things, 

 or carry on a variety of processes. Chief among 

 these are the absorption of material from which food 

 is to be formed from the soil and air ; the conversion 

 of these substances into compounds suitable for stor- 

 age, transportation, or use by the protoplasm; the 

 assimilation of the food into the living substance, 

 building iq) and enlarging its hoAj, storing up surplus 

 food for future use, conducting water and other mate- 

 rial from one part of its body to another, digesting 

 the reserve material, such as starch, when needed for 

 food, breathing, throwing away the worn-out and 

 useless material, holding the body in the proper posi- 

 tion, and finally, and most important of all, taking 

 care that the species is preserved by giving rise to 

 new individuals by means of spores, seeds, runners, 



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