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Planta

, Volume 91, Issue 3, pp 181–189 | Cite as

The state of the pores in functioning sieve plates

  • A. W. Siddiqui
  • D. C. Spanner
Article

Summary

Electron microscopy of Helianthus stem and Saxifraga sarmentosa stolon after first plunging the material into boiling water indicates that the natural condition of the sieve plate pores is to be plugged fairly compactly with slime substance. Electron microscopy of pre-wilted plants demonstrates the same thing. These and other arguments indicate that the slime-filled condition of the pores is not an artifact induced by enzyme action or turgor release, nor is it a consequence of rapid translocation of slime; it is the natural state. This conclusion, very damaging to the pressure-flow hypothesis, is favourable to the electroosmotic theory.

Keywords

Enzyme Microscopy Electron Microscopy Enzyme Action Boiling 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Springer-Verlag 1970

Authors and Affiliations

  • A. W. Siddiqui
    • 1
  • D. C. Spanner
    • 1
  1. 1.Bedford CollegeLondon

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