Fig. 5.

Filament lengths and forces necessary to buckle the elongating filaments. (a) Summary of final filament length determined by summing the distance the bundle tip was held away from the wall (shaded regions) and the filament elongation measured from the bead displacement (unshaded region) for 11 experiments. (b) Observed average force at stall (■) determined from bead displacement, compared with the force necessary to buckle a single filament (cross) as determined from the length in a. Vertical axis is as in a.