PLANT CELL MEMBRANES 



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Figure 112. A-D, Cellulose ring and cellulose fibril formation in the developing 

 chloroplasts of Valonia ventricosa (500 X). E, Removal of plastid membranes 

 from two plastids and washing away green plastid plasma makes rings and fibrils 

 more clearly visible (625 X). F, After removal of plastid membranes mature 

 fibrils straighten and readily break into cellulose particles (700 X). G, H, Fibrils 

 uncoil from plastids on inner surface of membrane and align themselves with 

 fibrils in developing membrane (G, 625 X; H, 700 X). J, Orientation of fibrils in 

 mature membrane as shown by microscope and X-ray diffraction (700 X). 



