Plant organs exhibit, as we have already seen, a heliotropic curvature under direct stimulation.
This heliotropic sensitiveness lasts only as long as they are not fed.
heliotropic reactions play a great rle in the preservation of individuals as well as of species.
This reflex process agrees in every point with the heliotropic effects of light on plant organs.
We must therefore conclude that the heliotropic curvature of the polyps is determined by a photochemical action of the light.
The eyes of this heliotropic machine consist of two lenses in whose focus is situated the retina consisting of selenium wire.
If the cotyledon be shaded and the light be permitted to fall on one side of the hypocotyl, no heliotropic curving takes place.
The growth or movement of a fixed organism, especially a plant, toward or away from sunlight. Heliotropism can be easily seen in sunflowers, which slowly turn their large flowers so that they continually face the sun.
heliotropic adjective (hēl'lē-ə-trō'pĭk, -trŏp'ĭk)