27 research outputs found
Gravity "Perception" by Non-Specialized Structures.
Experiments on gravity effects in biological systems demonstrate that gravity can be perceived and used to modify functions even if there are no specialized organs or structures. We will have to look for ubiquitous structures which may interact with gravity. Theoretical investigations of the membrane-solution system indicate density variations in the fluid phase near the membrane surface. Together with related concentration and potential variations the membrane-solution interface turns out to be a structure for which gravity effects may be postulated. Some of these effects and the limitations of the theory will be discussed in detail
Gravity Effects on Biological Systems.
Theoretical investigations of the membrane-solution interface predict different effects on vertically and horizontally oriented planar membranes. Single channel events of gramicidin incorporated into phosphatidylserine planar bilayer membranes were measured in 0.1 M KCl solution, pH 7, at room temperature. The potential difference across the membrane was set to +- 70 mV. The mean channel current was observed to be about 20 % higher in horizontally oriented membranes compared to vertical membranes. This is in good agreement with the theoretical considerations and demonstrates that gravity doedoes affect membrane processes by interaction with the membrane- solution interface which is a ubiquitous structure in biological systems
Effects of Gravity on Early Development.
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