ISSN:
1432-1904
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
,
Natural Sciences in General
Notes:
Abstract Paramecium generates persistent shifts of the membrane potential of a few millivolts depending on its orientation with respect to the gravity vector. The resulting potential-induced modulation of the speed of propulsion is called gravikinesis because it acts to neutralize, fully or in part, sedimentation. Gravisensitivity is maximal at neutral orientation, i.e., in horizontally swimming cells, when the gravitational force per unit membrane area is at minimum. Stimulus-response relationships and energetic considerations show that sensing of the gravity vector by a nonspecialized, single-cell organism ranks among the most sensitive mechanoreceptors known in nature.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s001140050634
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