ISSN:
1432-072X
Keywords:
Electron microscopy
;
Euglena mutabilis
;
Flagellate
;
Photomovement
;
Photoreceptor
;
Phototaxis
;
Single-cell analysis
;
Videomicroscopy
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract Due to the lack of an emergent flagellum the green flagellate Euglena mutabilis is restricted to gliding motility. During forward movement, the organisms orient positive phototactically in the presence of a suitable light stimulus. The cell contains both a stigma and a paraflagellar body which differ in shape and size from the organelles found in E. gracilis. The degree of orientation in white light follows an optimum curve with a maximum at about 100 lx. The spectral sensitivity shows a number of prominent peaks in the blue and green regions and extends well into the red region of the visible spectrum. Since the cell does not rotate during locomotion a periodic shading mechanism cannot account for phototactic orientation. Thus, phototaxis in the related species, E. gracilis and E. mutabilis differ in their photoreceptor molecules, their sensory transduction chains and their strategies of light direction detection.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00419477
