PHYSIOLOGICAL CHARACTERIZATION OF GRAVITAXIS IN EUGLENA GRACILIS

摘要

The motile, unicellular freshwater flagellate Euglena gracilis uses external stimuli, like gravity, light or oxygen pressure in order to orient itself in its natural habitat. In the darkness the cells normally show a negative gravitactic behavior, that means they swim upward in the water column. Many ground and space experiments revealed that gravitaxis is most likely based on active physiological mechanisms (involvement of calcium, cAMP, membrane potential and other parameters).