204 THE INDIVIDUAL ORGANISM 



prey is digested by special enzymes and furnishes nitrogenous substances 

 to the plant. 



Our survey of the chief patterns of plant life has shown that, including 

 those plants that lack chlorophyll, all plants, from the simplest to the 

 most complex, are faced with the same basic problems. They solve these 

 problems in various ways, as do animals, depending upon their degree of 

 organizational complexity and the particular circumstances in which 

 they live. We can go even further than this; in spite of the superficial 

 dissimilarity between plants and animals, we are now in a position to 

 realize that the fundamental requirements for living are the same for all 

 organisms. Plant or animal, the organism must have access to water, it 

 must obtain food, it must have means of releasing energy from that food 

 (in the enormous majority of organisms, by means of oxidation), it must 

 be able to rid itself of wastes, it must be able to respond appropriately to 

 changes in its environment, and it must be able to reproduce. The types 

 of organization characteristic of plant and animal are adapted to accom- 

 plish these things in different ways. 



