Fig. 4.

Gravitropism with a rotating base. (A) A base is tilted with respect to the vertical and then rotated about the axis with speed so that one revolution is completed every time unit. Gravitropic response is simulated for varying values of gravitropic sensitivity ${\mathcal{C}}_{\text{grav}}=0.1$ (black), 1 (red), 10 (green), and 50 (blue). (B and C) Alignment with the vertical (B) and curvature and torsion (C) are plotted against time for three base rotations. (D–F) Snapshots for cases of (D) slow reaction, ${\mathcal{C}}_{\text{grav}}=1$; (E) intermediate reaction, ${\mathcal{C}}_{\text{grav}}=10$; and (F) fast reaction, ${\mathcal{C}}_{\text{grav}}=50$. The sequence is read left to right, top to bottom, and the base rotation is counterclockwise. Further simulation details and parameters are provided in SI Appendix, section 8.