Metabolism and mode of action 



directly dependent. Osmotic concentration of coleoptile section tissue does 

 not appear to be influenced in any direct way by auxin. Auxin appears 

 rather to increase diffusion pressure deficit by lowering cell-wall pressure, 

 although the d.p.d. gradient which governs water movement into the cell is 

 so small that it has not been possible to measure it directly. 



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Bonner, J., Bandurski, R., and Millerd, A. (1953). Linkage of respiration to 

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Burstr6m,H. (1953a). Studies on growth and metabolism of roots. IX. Cell elonga- 

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Burstrom, H. (1953b). Growth and water absorption of Helianthi/s tuber tissue. 

 Physiol. Plant. 6, 685. 



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