DIVISION I. 



THE STRUCTURE AND PROPERTIES OF THE 

 PROTOPLASM OF PLANTS. 



PROTOPLASM, like every other substance, exhibits a distinctive 

 physico-chemical structure, composition, and properties. But 

 in addition it possesses also some unique qualities correlated 

 with its vital activities, and these involve remarkable relations 

 with the external world, including the important power of build- 

 ing organisms. Hence the study of this division of Physiology 

 falls rather readily into sections as follows: 



Section i. The physical structure and properties of Proto- 

 plasm. 



Section 2. The chemical composition of Protoplasm. 



Section 3. The vital structure and properties of Protoplasm. 



Section 4. The reactions of Protoplasm to external forces. 



Section 5. The building of organisms by Protoplasm. 



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