CHAPTER VIII. 



HOW SOME PLANT PARTS REMAIN RIGID. 



82. Turgidity of plant parts, In Chapter VI we found that 

 the turgescence of a cell depends on the absorption of water by 



Fig. 34- Fig. 35. 



Indian turnip plant just removed from the Same plant half an hour later. It is be- 

 soil. It is rigid. coining limp. 



protoplasm. The protoplasm permits the cell-sap to draw the 

 water inward by diffusion, but the protoplasmic membrane does 

 not permit the water to filter out readily, and the outward pressure 



45 



