Phototropic Inversion in Phycomyces.

Transient reversed bending follows an adequate step-up in light intensity given a bending cell from any direction around its axis, yet the plane of the response is specifically that in which prior phototropic bending occurred. The cell "remembers" what it was doing and reverses this in the ensuing light-growth response. Antecedent asymmetric growth itself built the pattern for reversal.