CHAPTER THIRTY-SIX 



THE NON-GREEN PLANTS 



The green plants are called autophytes (Greek : autos, self, and 

 phyton, plant), because they are independent or self-supporting. 

 Given sunlight, they can make their own food from water, carbon 

 dioxide, and mineral salts. 



There are, however, great numbers of plants that lack chloro- 

 phyll and hence are not able to make their own food. Many 

 of them, like the bacteria and yeasts, are microscopic in size; 

 others, like the molds and mildews, are small but visible to the 

 unaided eye; still others, like the puffballs, mushrooms, the 

 bracket fungi that are seen on trees and logs, and the Indian 

 pipe of the forest, reach a size comparable with that of many green 

 plants. 



Energy necessary for life. In the study of biology it is well 

 to have in mind always that a perpetual-motion machine is no 

 more possible in the living than in the non-living physical world. 

 A living organism must have energy to carry on its activities 

 and life processes. Green plants, non-green plants, and animals 

 are alike in requiring an energy income for their life activities. 



As we have seen, the green plant secures its energy from the 

 sunlight. The energy of the light is not used directly in the 

 operation of the vital mechanism, but it starts synthetic processes 

 within the plant that end in the complex compounds we call 

 " foods." These are then oxidized, and the energy required by 

 the plant is released in the breaking-down process. 



Lacking chlorophyll, non-green plants cannot use the sunlight 

 in synthetic processes. They must, therefore, secure their energy 

 from materials already built up so that it can be oxidized. 

 This the great majority of them do either by living directly 

 on other living organisms or by feeding on dead organic matter 

 originally synthesized by green plants. 



378 



