A Unified Model of Shoot Tropism in Plants: Photo-, Gravi- and Propio-ception
Figure 3
A. Timelapse of a coleoptile during phototropic movement, 50 minutes between each picture.
The source light is collimated on the right of the organ and is perpendicular to the vertical. The white bar is 1cm. B. The kinematics of the angle A(s, t) plotted with respect to time t and curvilinear abscissa s (from the base to the apex of the organ). C. The kinematics of the curvature C(s, t) plotted with respect to time t and curvilinear abscissa s (from the base to the apex of the organ). At first, the whole organ curves; then the curvature concentrates near the base.