THE ASCENT OF SAP 



261 



pressure will be lowered and this cell, A, will have a lower osmotic 

 pressure than cell B (see Fig. 16). That is, there is a higher con- 

 centration of water in A than in B and water will go from A to B. 





Fig. 16— Illustrating the path of 

 water through the plant. For ex- 

 planation see the text. 



Cell B will then have a lower osmotic pressure than C and water 

 will pass from B into C. Thus is established the osmotic gradient 

 mentioned above. 



