Fig. 2. Induction of rapid growth by the acute addition of laminin. DIC recording of growth from a neuron plated on a fibronectin substrate that was then exposed to laminin. By 20 minutes after the addition of laminin, veils of membrane have appeared on the thickened shafts of filopodia (arrows). By 25 minutes, the large-spread growth cone has given rise to a thin process with a smaller growth cone. Bar, 10 µm.