Contents 



Foreword 



H. C. I. Rogers 



Preface 



J. E. Harris 



The present position in the field of facilitated diffusion and selective active 

 transport 



J. F. Danielli 



Cholinesterase and active transport of sodium chloride through the isolated 

 gills of the crab Eriocheir sinensis (M.Edw.) 

 H. J. Koch 



Discussion on papers by Danielli and Koch 



Membrane structure as revealed by permeability studies 

 H. H. Ussing 



Discussion 



The ionic permeability of nerve membranes 

 R. D. Keynes 



Discussion 



Cellular oxidations and the syntheses of amino-acids and amides in plants 

 E. W. Vemm 



Discussion 



The biosynthesis of pentoses and their incorporation into mononucleotides 

 H. Klenow 



Discussion 



Deoxynucleic acid in some gametes and embryos 

 E. Hoff-Jorgensen 



Discussion 



Nuclear control of enzymatic activities . . 

 J. Bracket 



Discussion 



The cell physiology of early development 

 C. H. Waddington 



Page 



v 



vn 



^5 



27 

 33 

 41 

 43 



49 

 5 1 



64 

 67 



78 

 79 



88 

 9i 



102 

 105 



IX 



