Plants Breathe 



with the likes and dislikes of even the commonest 

 garden plants individually, yet there are certain 

 facts that are true for all plants alike, and, bearing 

 them in mind, the cultivator can approach the 

 attempt to cure or prevent disease with some hope 

 of dotag it intelligently. 



A plant is a complex organism every part of 

 which has its own functions to perform, and its own 

 special requirements to enable them to be performed. 

 There is one function, however, which is performed 

 in every part of the plant body which is alive. 

 Every part of the plant breathes ; that is, every part 

 of the plant takes in oxygen from the air, and gives 

 out carbonic-acid gas into the air. The gases pass 

 through the delicate walls of the youngest roots, 

 through special openings called lenticels on older 

 roots and woody stems (they can be easily seen on 

 smooth stems as light specks on the bark), and 

 through minute openings in the skin of leaves and 

 young stems, which can be opened or closed at need, 

 and which are called stomata. Provision is made 

 all through the plant by means of spaces between the 

 cells of which it is composed for the air to pass freely 

 to every part. Water-plants obtain oxygen from 

 that dissolved in the water which surrounds them ; 

 all others obtain it directly from the air. Breathing 

 is as necessary to plants as to animals ; fresh air is 

 as necessary to a plant as to a fire. Breathing goes 

 on whenever the plant is active, and the more active 



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