ABSORPTION AND MOVEMENT OF WATER 151 



travels in the plant, and describe an experiment proving your statement. 

 (1897.) 



(8) What is the chief function of the wood? Give experimental 

 evidence in support of your answer. (1891.) 



(9) Explain what is meant by "root-pressure." What manifestation 

 of it occurs in nature? (1892.) 



(10) Give an account of the absorbent organs of roots, and of the 

 process of absorption. (1892. ) 



(11) The trunk of an Oak tree, when in full leaf, is sawn all round so 

 deeply as to cut through the sap-wood. State and explain the effect of 

 this operation. (1893.) 



(12) Describe the effect of a tight ligature upon a growing hazel 

 stem. 



(13) What is meant by transpiration? In what circumstances do 

 plants transpire most? (jive experiments which demonstrate how 

 transpiration takes place. 



(14) Why does a branch when removed from a plant begin to flag? 

 How may this be prevented ? (1885. ) 



