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Science 17 December 1971:
Vol. 174. no. 4015, pp. 1237 - 1240
DOI: 10.1126/science.174.4015.1237
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Articles

Direct Test of the Positive Pressure Gradient Theory of Pseudopod Extension and Retraction in Amoebae

Robert Day Allen 1, David Francis 1, and Robert Zeh 1

1 Department of Biological Sciences, State University of New York at Albany, Albany 12203

When one pseudopod of an amoeba is sucked into a capillary connected to a partial vacuum and subjected to a pressure reduction of 30 to 35 centimeters of water, extension of other pseudopods, exposed to atmospheric pressure, is not prevented. This result is interpreted to mean that cytoplasmic streaming cannot be the result of a positive pressure gradient generated along the length of the stream, for if it were, streaming would have reversed its direction under the applied pressure gradient of opposite sign and supposedly greater magnitude.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Low frequency electric field induced changes in the shape and motility of amoebas.
A. Friend Jr, E. Finch, and H. Schwan (1975)
Science 187, 357-359
   Abstract »    PDF »
Capillary Suction Test of the Pressure Gradient Theory of Amoeboid Motion.
T. L. Jahn, J. J. Votta, G. S. Kirby, R. A. Rinaldi, I. L. Cameron, R. D. Allen, R. Zeh, J. Condeelis, and D. W. Francis (1972)
Science 177, 636-638
   PDF »


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