..., of gravitaxis. To rotate the body upwards, cellular asymmetry is critical. Chlamydomonas can be depicted as a nearly spherical cell body with two anterior, symmetric flagella. The present study looks at the question of whether the existence of the flagella significantly affects torque generation in upward...

.... Published by The Company of Biologists Ltd 2013 bioconvection phase transition gravitaxis gyrotaxis Bioconvection is a phenomenon of macroscopic pattern formation that occurs as a result of the collective motion of swimming microorganisms. In a homogeneous suspension, swimming activity...

...A. M. Roberts SUMMARY An analysis of swimming patterns in the ciliate Paramecium shows that the ability to swim preferentially upwards (negative gravitaxis) is primarily the result of upwardly curving trajectories. The trajectory characteristics are consistent with those produced by mechanical...

... chamber into the vertical position allows the cells to orient with respect to gravity. A statistically secured majority of cells walk antiparallel to the gravity vector although this behaviour is not predominant (negative gravitaxis; r O =0.06; P ≤5%). As might be expected, no preferential orientation...

...Ute Nagel; Hans Machemer ABSTRACT Wild-type and the morphological mutant kin 241 of Paramecium tetraurelia showed improved orientation away from the centre of gravity (negative gravitaxis) when accelerations were increased from 1 to 7 g . Gravitaxis was more pronounced in the mutant. A correlation...

...Richard Bräucker; Akira Murakami; Kazuko Ikegaya; Kenjiro Yoshimura; Keiichi Takahashi; Sigrun Machemer-Röhnisch; Hans Machemer ABSTRACT The kinetics of gravitaxis and gravikinesis in Paramecium caudatum were investigated by employing (1) step transitions from normal gravity (1 g...

...) enhanced the negative gravitactic and the gravikinetic responses in Paramecium biaurelia within seconds. Cells did not adapt to altered gravitational conditions. Repetitive stimulation did not change the graviresponses. The minimum acceleration found to induce gravitaxis was between 0.16 and 0.3 g...

... gravitaxis was documented. Such behaviour incorporates distinct acceleration-dependent orientational and velocity responses, keeping populations of cells stationary in the gravity field (taxis coefficients close to zero). Median sedimentation rates of Ni 2+ -immobilized Didinium are a linear function...

..., desensitization of mechanosensory channels and hyperactivation of ciliary activity in straight swimmers. * To whom reprint requests should be addressed. 23 9 1991 © 1992 by Company of Biologists 1992 Paramecium caudatum hypergravity swimming velocity gravikinesis gravitaxis...